Bailey, Boyle, Bray, Byrne, Carroll, Clacy, Fecker, Ferson,
Gardam, Gaertner, Howard, Jaegers, Martz, Petitdidier, Sellew,
Spencer, Thomson, Tinsley, Tolles, Usner, Witherspoon
==================================================
BAILEY
Henry Page Bailey (b. Wisconsin, 21 August 1883; d. 1962); studied dentistry
& built an X-ray machine at USC, received degree in 1911, then moved to
Riverside, California. In 1926, in exchange for dental services, he acquired a
15 inch glass blank with which he built a Cassegrain telescope.
An 8 inch mirror by Bailey was mailed to Caltech's John Anderson in the
early 1930s, and the reply noted that the high quality of the optics was
witnessed by Russell Porter & Anderson; and offered one of the new aluminum
coatings by John Strong, for Bailey to test in his astrophotography work.
Circa 1930, he designed the 'horseshoe' mounting, adapting the English mount
by making the upper bearing a wide ring so that the telescope tube could point
directly at Polaris. Apparently a first version was built of wood, with a 12
inch telescope, but the only evidence is one surviving photograph. The first
substantial and confirmed example was built by Bailey using part of a truck
chassis, set in concrete, holding two piers, the tall northern pier with two
roller bearings and the shorter southern pier with a single ball bearing. The
bearings carried a rectangular yoke of steel channel, which at the northern end
was open and attached to a wide horseshoe shaped bearing surface riding on the
roller bearings. This horseshoe was wide enough to circumscribe the telescope
tube, which could therefore point at the pole and slightly below, though there
was still an area of sky near the pole that was visible only part of the night.
The tube was built of wood over hoops of steel, and used the 15 inch Cassegrain
optics with a diagonal tertiary to direct the light to the side. An electric
drive was built from a synchronous motor taken from a phonograph; and the worm
drive at the south polar axis used a friction plate to allow manual motion
while the motor was running. The observer was stationed in a pit dug under the
instrument & lined with corrugated iron. It was sheltered by a shed with a
slanted, counterbalanced roof that opened on a hinge set near the floor to the
south. Completed in early 1931. Photos of the 15 inch can be found in Sky &
Telescope v101 #3 (3/2001) 130, and in Scientific American 146 (1932) 308
(reprinted in the ATM series of books).
Photos were mailed to Russell Porter at Cal Tech, who was working with John
Anderson on the future Palomar telescope; both men visited Bailey in spring
1931 and approved of the mount.
San Bernardino Junior College (now S.B. Valley College) includes the N.A.
Richardson Observatory. Director Frank Lindsay had solicited Porter &
Anderson's opinions on the mount for use with Richardson's 16 inch mirror by
John Mellish (at that time in a telescope acquired circa 1930). For Lindsay,
Bailey built a Cassegrain secondary, the telescope & components, and an
improved mounting with a hollow cast iron yoke, made extra sturdy to hold a 24
inch telescope that was never realized. This telescope was also examined by
Porter & Anderson, and the observatory, with one of the first all metal domes,
was dedicated in October 1931. After about 30 years of use, it was
disassembled; then in the 1970s the observatory was restored and used until the
late 1990s.
The Richardson cast iron model was copied by Bailey for a replacement
mounting for his 15 inch telescope, completed near the end of 1932. A drive
gear 22 inches in diameter of cast iron used a clutch with animal hide as a
friction pad. A Griffith Observer from 1937 has an early photo, with brackets
on each declination bearing, holding a Schmidt camera on one side and a 12 inch
Newtonian on the other. This mount was restored by Allan Guthmiller circa
1999, although parts including the drive gear were ruined, and it now houses a
20 inch mirror. It is shown in Sky & Telescope v101 #3 (3/2001) 126-131.
A horseshoe mount was made by Bailey for his friend M. Nagata, Brawley
Calif. Photos of the scope appeared in Scientific American, in the January
1936 'Pacific Star Gazer', and a photo showing it in a roll off roof
observatory is in a museum in Brawley.
Photos show another small horseshoe mounting, possibly from an unknown
instrument.
Scientific American from 1932-3 shows a photo of a Bailey mount, or a model
of a mount, with two horseshoe bearings, designed for long focus refractors.
Some months after Porter and Anderson's first contact with Bailey, the
horseshoe design was considered for use on the 200 inch telescope. This was
not discussed with Bailey at that time, nor when the basic design was chosen in
1936, and credit was never extended to Bailey for his design. Albert Ingalls
heard rumors of a 19th century mount that was similar to the horseshoe or the
split ring mount, but was not successful in researching this precedent. (Henry
Russell of Sydney Observatory, Australia, published such a design in 1879, and
then fabricated a mount very similar to Bailey's.) Bailey was not the first to
invent this configuration, but he derived it independently and apparently was
the inspiration for the mount used at Palomar. There is a record of a
notarized photo and model of the mount, that were evidence of Bailey's desire
to establish priority, and contemporaries of Bailey tell of his unhappiness at
being denied credit for the idea.
Bailey was the first person in the U.S. to fabricate a Schmidt camera, and
the second person after Schmidt. Don Hendrix of Mount Wilson had begun a
Schmidt, and in 1932, gave a lecture to an amateur astronomy group, which
inspired Bailey to begin. He completed it in early 1932, first mounting it on
top of the 15 inch Cassegrain tube in the steel horseshoe mount; and in late
1932, remounted it on a platform on the second cast iron mount. He offered
this camera as a donation to Griffith Observatory in 1962, but the offer was
declined and since 1974 it is catalog number 334,722 in the National Museum of
American History at the Smithsonian, where it is in fair condition. The mirror
is 9 1/16 inch diameter, spherical, 1.5 inches thick, (f/2.5 or 19 inches
focus, different sources). Corrector plate is 9 1/16 inch diameter, 11/64 inch
thick at edge, with a red alignment mark on the edge. It was stopped down to 8
inches in use. Optics are mounted in a plywood box 15 inches square by 52
inches long, with a steel mirror cell. The mount is made from an automobile
frame. The Schmidt is shown in Ingalls' ATM Advanced, Book Two, page 397,
mounted on the 15 inch Cassegrain, but the Schmidt tube was a cylindrical,
partially open frame at that time. In the 1996 edition of the ATM book series,
vol. 2 p444, Harold Lower describes Bailey's method of fabricating a Schmidt
corrector, using subaperture tools with 1/2 inch squares of glass cemented to a
sponge rubber base.
In 1947, Mabel Sterns published her directory, including: 'H. Page Bailey,
3925 Crestmore Avenue, Riverside, Calif. Observatory is in the form of a pit
lined with corrugated iron. Built 1932. Inactive. 15-inch reflector, F.L. 78
inches, with setting circles and motor drive. Bailey mounting, forerunner of
Palomar mounting. 9-inch Schmidt camera.'
In the 1950s, Bailey hosted local amateurs, and at the time owned:
--15 inch Cassegrain (still over the pit), and a long focus folded solar
telescope
--The Schmidt camera, unused and not mounted.
--9 inch Newtonian, shown in ATM Advanced, p. 315, an open truss tube, mounted
on a short version of the horseshoe with an electric drive.
--A solar telescope, with a primary about 4 inches diameter, wedge shaped,
unsilvered, long focus. A flat at the opposite end folded the path, with the
eyepiece by the primary. Mounted on an English yoke.
--------------------------
Bailey text is based largely on email from Anthony Cook, Steven Turner, Bruce
Sayre, and Christopher Clarke; May, 2001.
Cook, Anthony. H. Page Bailey: A Pioneering Telescope Maker. Sky & Telescope,
March 2001, p130-1.
Pacific Star Gazer. January 1936
Scientific American: see quoted text below.
There are numerous references to Bailey in the three volume set 'Amateur
Telescope Making', published by Scientific American in the 1920s through the
1970s, and reprinted by Willman Bell in 1996. The first publications were
edited over time and pagination is not consistent, and the 1996 edition is
completely reorganized. Citations are therefore confusing.
ATM Advanced, vol. 2, p. 317, telescope drives.
ATM Advanced, vol. 2, 7th printing, 1949, photos on p315 & p397.
ATM volumes 1-3 (1996): 1-514, photo 15 inch Cassegrain. 2-250, photo 9 inch
Newtonian. 2-428, photo Schmidt camera. 2-444, note on fabricating Schmidt
corrector.
Sterns, Mabel. Directory of Astronomical Observatories in the United States.
Ann Arbor: J.W. Edwards, 1947.
--------
Scientific American v146 (May 1932) 308-9. Ingalls, ATM. Photo of 15 inch
Cassegrain. (reprinted in the ATM series of books). Follow up, August 1932.
Scientific American, February 1933. Albert Ingalls: "DR. H. PAGE BAILEY, the
Riverside, California dentist who designs and makes a new telescope every
morning, has constructed for M. Nagata (discoverer of Nagata's Comet) a neat
nine-inch electric-clock-driven reflector of the split ring equatorial type.
This type of mounting is unusually trim, compact, and mechanically superior,
its operation being very smooth. Note the neat, accessible hour circle on the
face of the ring. Dr. Bailey has originated a unique mounting for a refractor
or reflector, shown in the illustration above (model only) in which there are
two split rings, each on rollers, one bearing down on its exterior, the other
up on its interior. The tube is self-balancing. As no pier is in the way
there is no reversing, and there are no blind spots in the sky. Russell W.
Porter says he believes this mounting is wholly original with Dr. Bailey. The
split equatorial ring principle itself was first embodied in a telescope by Mr.
Porter when he made, in 1922, about 50 of the well-known "Porter Garden
Telescopes" having this feature, the ring turning on rolls. It is a pleasing
design and might have been embodied in the 200 inch telescope, but it was found
there was no way to get the big mirror in and out! A photograph of the Orion
nebula made by Dr. Bailey with a similar telescope (an eight inch of f 3.6) is
reproduced. The photograph, which was made by placing a plate holder in the
primary focus and exposing 18 minutes, covers a field about a quarter degree in
width; note the absence of coma at the edge of the field! Those star images are
round."
Scientific American, March 1933: "Dr. H. Page Bailey of Riverside,
California, protests our description of his mounting (January number, page 51)
as a "Porter type." It is always hard to say just exactly what a design is,
because one type so often shades off into another. Bailey's mounting uses a
double yoke in connection with the Porter split ring, and so it's a Porter type
if you accent the ring and a Bailey type if you accent the yoke. As Porter has
not contested it, let's accent the yoke and all stay happy."
Scientific American v153 #3 (September 1935) p154. Albert Ingalls: "Here is
the dope on Borium: The Stoody Company, located in Whittier, California,
supplies Borium lathe tools, and with these you turn your curve in the glass
just as you would turn a disk of metal. A piece of Borium 1/2" x 5/8" is used,
and the glass is pitched to the face plate. Note picture on p. 156, sent by Dr.
H. Page Bailey of Riverside, California. Concerning it he writes, "It is a
revelation to see the glass scrape off -- just like scraping ice with a steel
tool. The tool I used on two 10" Pyrex disks doesn't even show any wear,
though it is slightly chipped." He roughed out two 10" Pyrex mirrors to a deep
curvature in eight hours -- 12 times the speed of Carbo work. 'In my opinion,'
Lower comments. 'Borium is the greatest advance in the art since the invention
of Carborundum.' Bailey sent us a Borium point-heavy metal, said by someone
else to be borium carbide. It proved easy to write on Pyrex with a sharp piece
of it -- sign all your mirrors. And the stuff is cheap, at that. Note the
shaved "ice" in Bailey's photo, in a snowbank beneath the tool. The metal is
shattered in a vise, a selected point is brazed, welded or silver-soldered into
a saw cut in the end of a drill rod, and dressed to a broad angle on a
Carborundum stone."
==================================================
BOYLE
Charles B. Boyle, New York city, 1860s - 1880s. Binocular telescopes.
1867, American Optical organized, with C.B. Boyle as optical director to
oversee manufacturing, 'a gentleman more thoroughly versed in optical science
and practical knowledge than probably any one in this or any other country'.
Either this association did not last, or Boyle ran his own business while at
AO.
4 1/4-inch finder scope at Cornell by Boyle.
Boyle, Charles B. Recent Improvements in Optical Instruments. no date,
N.Y.C. 3p. Binocular refractors; apertures to 17 inches (x2); diagonals rotate
to allow two people to view through the separate telescopes at the same object;
equatorially mounted with tubes in a rotating ring to keep eyepiece pair
horizontal. 6 inch f8 refractor with binocular viewer; one eyepiece off axis
& directed towards the center of the objective so that it is skew & views a
field adjacent to the other eyepiece: a comet seeker with double the field of
view; equatorial in rotating ring (built & claimed successful). Submarine
telescopes, for viewing the ocean bed, used under and above surface of water.
Stereoscopes, microscopes, spectroscopes.
Boyle, Charles B. Binocular Vision in Telescopes. Scientific American, June
12, 1880, pp370-371. Binocular microscopic telescope, auxiliary lens for focus
at 1 to 10 feet & use as microscope: "to the medical profession, the power to
bring under microscopic observation offensive diseases of the skin, while the
observer is yards away from the point under examination....The binocular
microscopic telescope has been presented before the N.Y. Microscopical
Society.....so that, as in the case of my double-eyed comet seeker, it is now
too late to declare its construction an impossibility."......"Thus repelled at
every point, I was forced to take up the practical construction of such
(binocular) telescopes, and found them not only easy of adjustment, but really
more than twice as luminous, for the simple reason that seeing with one eye is
mutilation, and a man can no more see half as well with one eye as he can with
two, than he can walk half as well with one leg as he can with two,
consequently our entire system of telescopic observation up to the present time
is mutilation, and a time is coming in the future when the heavens will render
up to binocular vision vast resources of knowledge which will be withheld from
man as long as he persists in squinting at them with one eye under the lofty
impression that he knows more about the relative value of the eyes than the
Cause that created him......The far off problems of space, and many of the
nearer ones, will remain unsolved until a generation arrives upon the planet
sufficiently in earnest to use the resources nature has endowed them with, and
who will comprehend that self-mutilation is not one of the stepping stones to
wisdom."
1865, patent 50,681, photographic lens
1866, patent 52,129, combining photographic lenses
1866, patent 52,672, lens
1867, Invented, patented, & exhibited 'ratio lens', constructed by Mr. Alvin
Clark. For copy & view cameras. 1867 ad in Philadelphia Photographer, ratio
lens 'manufactured solely by the American Optical Co.
1869 or 1870, at American Institute Fair, Boyle's model of the moon won
first prize, also wrote article 'On Lunar Formation', and an article on
binocular telescopes, for the AI times.
(DJW-NMAH)
==================================================
BRAY
Max Bray was born 21 May, 1912, in The Dalles, Oregon, and made his first
telescope mirror, a 4 inch f/8, at age 19. He began professional optical work
in 1933, at Tinsley Laboratories in Berkeley, Calif. After WWII began, he
moved to L.A. and founded the Bray Optical Company, to produce optical elements
for military purposes. Bray worked on camera optics for Mariner 4 in 1963, for
the first close up photos of Mars. In the early 1960s, optical engineer Donald
Perry designed a Maksutov Cassegrain, which Bray used for his 'Ad Astra' f/9.5
Maksutov, some hundreds of which were produced. Bray retired in 1982, but
produced custom telescopes from home, and was so engaged when he died May 30,
2000, in Phoenix, Arizona.
An article by Bray, 'How to Grind and Polish a Lens', can be found at Newport
Glass' web site:
http://www.newportglass.com/share.htm
A 20 inch f/10 Maksutov Cassegrain built by Max Bray and Ralph Nye (Lowell
Observatory), is at the Vega Bray Observatory, Arizona.
A 12 inch f/15 Maksutov-Cassegrain by Max Bray, is at McMath-Hulbert
Observatory, in Michigan.
===============================================================
BYRNE
John Byrne, apprenticed by Henry Fitz in 1847, & worked with him until Fitz'
death in 1863, then began making Byrne signed telescopes. Early Bryne
telescopes resemble those of Fitz, were undated, and were signed in script on
the faceplate above the focuser. In the 1870s and early 1880s, Byrne engraved
the lens cell in script. After the mid 1880s, the engraving was in script on
the faceplate. One objective is signed "JOHN BYRNE NEW YORK 1883" in block
letters. Most Byrne instruments are dated alongside the signature. Earlier
telescopes were f 15, and the later models were an innovation in being f9 to
f10.5.
Byrne made a 7 inch aperture telescope and claimed to have made the 13 inch
objective attributed to Fitz, for Columbia College, NY (later Columbia
University). A 5 inch Byrne was used by Barnard to discover many comets.
Byrne refigured at least one objective by another maker, owned by University of
Michigan.
Byrne was making objectives for tubes made by Gall & Lembke by April 1892,
signed on the lens cell and not dated. They were short focus instruments,
f/8.9 to f/10.5, and advertised as "Short focus and brilliant light"
telescopes. By January of 1899, the catalogs stated: "These instruments are
made of either long or short focus, according to the desire of the purchaser,"
however no telescopes of the standard f/15 specification are known. (From
notes by Robert B. Ariail)
=================================================
CARROLL
B. 1902, Belton, Texas; viewed Halley's comet in 1910; worked in aviation
1920s-30s, to Lockheed 1940s-60s. Made first, 6 inch reflector, 1938.
George A. Carroll, California, mid 1950s to early 1970s, making high quality
4 inch refractors, mountings and solar instruments. With Rex Bohanan, (Carroll
and Bohanan), in the mid 1950s, made precision instruments, including an 8.5"
F/18, and a 16" reflector. Carroll designed heliostats for Thomas Tool & Die,
Los Angeles area. He made solar spar telescopes for Hal Zirin at Robinson Hall
of Cal Tech, and for the San Fernando Solar Observatory of the Aerospace Corp.
(late 1960s and early 1970s). In the early 1970s, Carroll worked with the
Lockheed Solar Observatory, and constructed an instrument described in detail
in the July, 1970, Sky & Telescope. Designed & built the 30 inch reflector for
Stony Ridge Observatory, with an original & successful chain drive, used to map
lunar landing sites for Apollo missions. Built & donated a 16 inch telescope
to Westmont College, Santa Barbara. Carroll's business was probably purchased
by the Carlson Instrument Company.
Biographical notes on George A. Carroll. Proceedings 23rd Annual Convention,
Western Amateur Astronomers. Hawaii, 24-26 August, 1971.
Notes by John Briggs, Jack Eastman, and Bob Goff.
=====================================================
CLACEY
John Clacey was born in Massachusetts in 1857. As a young man, Clacey
ordered books and glass blanks for a six inch doublet, and in teaching himself
lens grinding, by repeated failures reduced the blanks to a thinness that
caused them to flex while being worked. He was forced to order another pair of
blanks and with these made a successful telescope and began developing his own
techniques of local correction followed by testing with an artificial star, for
he did not believe that following the mathematical formulas of lens designers
gave him a satisfactory product. He made instruments designed by S. C.
Chandler: the almucantar (used to detect the variation of latitude) and the
chronodeik (used to determine true local time). Clacey set up shop in
Cambridgeport, and made many refractors of three, four, and five inches
aperture, and over time made them of shorter focus, such as four inch f10
models, and one five inch f4.2. These were sold to amateurs and to the
U.S.N.O., the Coast & Geodetic Survey, the Blue Hills Meteorological Obs.,
Brook's Smith Obs., the Japanese Navy, and others.
Science Observer, 1877-87, printed an advertisement from Clacey as a maker
of achromatic telescope objectives of any size or focal length, and of the
finest quality.
Sidereal Messenger, 1 (1882) p201, published this note: "Mr. John Clacey of
Boston is now making for Mr. E. Sawyer of Cambridgeport a four and three-
eighths inch refractor. He has just completed one of six and one-fourth inches
aperture for Mr. Chandler which is mounted in the west dome of Harvard College
Observatory. Competent judges pronounce it to be an excellent instrument. Mr.
J.O. Tiffany of Attleboro, Mass. has a six inch telescope by the same maker."
Sawyer's telescope is also mentioned in Sidereal Messenger 1 (1883) p269.
Circa 1895, Clacey made two twelve inch objectives for Georgetown U., for a
Saegmuller equatorial mount; the first being rejected as defective, and both
still exist, the first lens having been recently found in storage. This twelve
inch was to be housed in a dome used for a smaller telescope, and its focal
length was limited to twelve feet. Saegmuller and Clacey worked together to
improve their instruments. A nine inch lens for Georgetown's photographic
transit telescope, and two six inch objectives for the collimator used with the
transit, were also made circa 1895.
A telescope at Amherst College Observatory, is reported as 10 or 12 inches,
said to be by Clacey and to be corrected for blue (photography), which was
piggybacked on the 18-inch many years ago, and found unmounted in an aluminum
cell with no surviving tube, in storage in the 1970s and 1980s.
Comet hunter William Brooks asked him to make a ten inch f10 for his Smith
Observatory, and Brooks reported that the color in the image was much less than
he expected and did not in the least interfere with definition.
Catholic U. of America purchased a nine inch objective.
A nine inch objective was made for Jesuit College, Aix-la-Chapelle, France.
Nine inch: (22.7cm, 280cm focal length). Aluminium tube & mount by Georg
Nicholas Saegmuller, exhibited at Worlds Columbian Fair of 1893, Chicago, then
mounted at St. Ignatius Jesuit College of Valkenburg in 1896. Used for
variable star work by Joseph Hisgen & Michael August Esch. Hidden in a
seminary in Maastricht during WW II, forgotten for over thirty years until
acquired by Sterrenwacht Schrieversheide public observatory, founded in 1976.
(Source, web site cited below)
Boston University has a 7-inch Clacey-objective telescope
Six and four inch lenses were made for the Vatican Observatory in Rome.
Six inch lenses were made for Harvard, Kirkwood Obs. at Indiana U., McGill
U. Obs., and St. Joseph's Convent in Manhattanville, N.J.
Clacey purchased property near Glendale, Maryland, to establish an optical
shop and as a site for his personal nine inch telescope. He accepted a job at
the National Bureau of Standards. During WWI, he developed methods for
grinding sextant mirrors to flat, parallel surfaces. "finishing one surface
plane and then cementing a large number of the small mirrors with the finished
sides down on a large optical flat. By watching the interference fringes
between the lower surface of the small mirror and the upper surface of the
flat, and by adjustment so as to keep the two surfaces parallel until the
cement had set, Clacey was able to produce sextant mirrors with only two or
three imperfect ones in a lot of thirty". During the war, he was the only
worker able to polish speculum mirrors found in naval instruments, experience
he had gained working for Harvard. Due to wartime restrictions on imports, the
NBS had begun production of optical glass, and Clacey made a 12 inch telescope
objective from this glass, the largest made from U.S. made glass, and used in
the laboratory at NBS. In 1926, Clacey made for the NBS three quartz flats of
10 inches diameter, 1.5 to 2 inches thick, flat to 1/100 of a wavelength (one
five-millionth inch).
References:
Popular Astronomy, 38 (1930): 472-7. John Clacey-Optician.
General Electric Review, vol 29 #8 (1926) pg 28.
Web site for Sterrenwacht Schrieversheide
Notes from: John Briggs, Tom Garver, Ken Launie, Deborah Jean Warner
====================================================
FECKER
Gottlieb L. Fecker's father and grandfather were instrument makers in
Carlsruhe, Germany; and his mother's family crafted optical products as well.
Gottlieb learned the trade at their small factory that produced precision
optical instruments, including telescopes; and at age 30 immigrated to the U.S.
with his wife, Emma Boccher Fecker. He worked for George Saegmuller in
Washington D.C. as a foreman, beginning before 1891, where his tinkering with
product lines created much conflict. Saegmuller wrote that he discovered
Fecker was copying drawings for Warner & Swasey, who imitated Saegmuller
designs for their astronomical instruments; and therefore dismissed Fecker
immediately. Gottlieb then worked at Warner & Swasey in Cleveland from 1895
until his death in 1921. He worked as a theoretical optician, instrument
designer, and was Superintendent of the instrument division until 1916, when
ill health forced him to retire from active employment, though he seems to have
retained an association for another 5 years. Gottlieb is credited with the 40
inch 'Automatic Dividing Engine' used at W & S, and the design & construction
of many of the other manufacturing tools. Many of the military instruments by
W & S are G.L. Fecker designs.
Gottlieb was the inventor of the improvements to prism binoculars that
became the patented Warner & Swasey binocular. U.S. patent 695,712 (1902) is
for a prism mounting system. 701,863 (1902) is for a prism housing cover of
flat plate metal that extends past the body to form strap loops, a design that
was quite common in European binoculars. 714,340 (1902), is for adjusting &
fixing the prism, a groove is cut in the side of the prism, with a metal finger
that engages the groove & is fixed by tightening a screw into the body.
He was father of James Walter Fecker, born in Washington DC, 04 March 1891.
Walter completed schooling at Case School of Applied Science in 1912. He then
spent ten years learning the craft from Gottlieb at W & S, including trips to
optical shops in Europe. Large telescopes by W & S from 1912 to 1922 were
computed, designed, and drawn by Walter; including drawings for the 72 inch at
DAO Victoria, 69 inch Perkins telescope, 60 inch for Argentina, Steward Obs. 36
inch in Arizona, and 12 inch for Cornell. He married Corinne Baffa in 1915,
and in 1921, at 32 years, he started his own business in Cleveland. Fecker
designed telescope systems and the machinery to build them, and manufactured
the optics and mechanisms for complete observatory systems. McDowell died in
1923, and in 1927 Fecker took over Brashear-McDowell. His first large job was
the 69 inch f4.3 for Perkins Observatory at Ohio Wesleyan U. In 1933 he
refigured the 60 inch f5.1 mirror by Common at Harvard & made a new mount for
it, which was then sent to Bloemfontein in South Africa. Paraskevopoulos
designed & made set of control rods to adjust figure of the primary for
different inclinations of the telescope. In 1934, he received an order from
Lick Obs. for a 20 inch f7.2 astrograph lens of the new four element Ross
design, using expensive special glass, and placed in a W & S mount; a project
that was still underway in 1940, but that resulted in an excellent camera that
produced a useable 20 degree field. 1937 brought the first large Fecker
telescope, the 61 inch f5.1 Wyeth telescope for Harvard's Agassiz station in
Mass., with Cassegrain - Newtonian optics and a fork mount. In 1940, he built
the 60 inch f5 for Warner & Swasey at Cordoba Obs., Argentina. As of 1940,
Fecker had built 80 telescopes of 4 inches aperture or larger, and many more
small instruments. He built a 28.5 inch reflector and a 15 inch horizontal
siderostat refractor for the private Cook Observatory, later moved to Flower &
Cook Obs. at Univ. Pennsylvania. Other Fecker instruments can be found at the
Bureau of Mines, Bureau of Standards, Calif. Institute of Technology, U.
Illinois, Kirkwood Obs. at Indiana U., McCormick Obs. at U. Virginia, Mt.
Wilson, U.S.N.O., Washburn Obs. at U. Wisconsin, Yale, and Yerkes. Also
designed & built the Copernican Planetarium at the American Museum of Natural
History.
There were two daughters, Helen and Ruth, who attended Smith and Vassar
colleges, and lived on 40 acres near Coraopolis, 15 miles from the factory.
Fecker belonged to the A.A.S., the R.A.S, and Sigma Xi. During WWII, the
factory was devoted to military contract work. Fecker died 11 November 1945,
leaving unfinished a 60 inch / 60 inch f2.5 Schmidt for Harvard. Fecker was
one of the first to master the Schmidt camera, producing Schmidts of apertures
including 16/24, 10/15, and 8/12.
J.W. Fecker Inc. continued, and built two 10 inch refractors (one for
Harvard), an 8 inch Maksutov for City College, N.Y.; the 24 inch at Arizona
State College, Flagstaff; and a 38 inch Cassegrain for Butler U., Indiana. The
company became a subsidiary of American Optical in 1956, and Joseph Kalla was
retained as president. Then followed a succession of owners, until 2000 when
the firm became Brashear LP.
Sources:
The Warner & Swasey Co., 1880-1930. Cleveland: W & S, 1930. p45.
The Sky v2 #12 (Oct. 1938) p3; Cook Obs. with photo of telescope.
Fisher, Clyde. James Walter Fecker, Builder of Telescopes. Popular Astronomy 54
(1946) 17-19.
Sky & Telescope, brief notes: vol. 5(Jan 1946) 7; and 16 (Dec. 1956) 73.
King, Henry. The History of the Telescope. High Wycombe: Griffin, 1955. p370,
395-6
Fried, Bart and John Briggs. Standing in Uncle John's Footsteps: James Walter
Fecker and his Legacy of Large Telescopes. Journal of the Antique Telescope
Society 16 (Winter 1999) 22-24.
Garver, Tom. Saegmuller notes for JATS article. 1999.
===========================
FERSON
Fred B. Ferson. Born 1897 in Galena, Ohio; moved to Mississippi in 1912;
graduated from Tulane U. in mechanical engineering, served in World War I,
worked in newspaper advertising and insurance. In 1933, he made a 6 inch
reflector, followed by a few other mirrors and flats. 1936, built a
Springfield mount: creating wood patterns; casting, machining and assembling
the metal parts, from plans provided by Russell Porter. Ferson then wrote a
text on how to fabricate the mount, for Ingalls' ATM book series. In 1941, the
imminent war motivated Ferson to quit his career and begin work as a
professional optician, teaching himself how to make the roof prisms needed for
military equipment. His experiences were the main source of technical
knowledge behind the 'Roof Prism Gang' of amateurs fabricating these parts
during WWII. Ferson also wrote long chapters on 'Lens Production', and
'Prisms, Flats, Mirrors' for later editions of the ATM books.
He founded Ferson Optics after WWII, originally to make amateur telescopes
and other optics. A three element refractor designed by Horace Selby of San
Diego was the first product, and was further improved based on consultations
with Selby. Since 1953 the company was based in Ocean Springs, Mississippi.
Increased government business during the Korean War caused the decision to
cease producing amateur telescopes. Ferson made quartz windows for
experimental aircraft and the Mercury and Apollo space capsules. Also made
were Baker design tracking cameras for White Sands and Aberdeen rocket testing
programs. Ferson optical flats, especially larger sizes, for the National
Bureau of Standards were considered by NBS to be the finest flats they owned.
Fred Ferson remained President until 1965, then chairman of the board; the
company was purchased by Bausch & Lomb in mid 1960s, when it had about 125
employees at two facilities. Ferson died April 28, 1969
Peter Lenart, Jr., was director of Ferson Optical; born in 1918, and in 1936
began amateur telescope making. During WWII, he was trained to maintain
artillery sights and sent to Normandy with the invasion, serving at front lines
and in Berlin. In 1946 began work with Ferson.
Ferson Optics 1216 telescopes, 16 inch aperture, f/4 Newtonian and f/14
Cassegrain foci; rotatable tube in a single fork mounting, digital readouts;
designed by Ferson engineer Shatzel; and costing $23,500 in 1967. 1216
Telescopes were sold to:
-Colgate U.
-Las Cruces.
-St. Marks Academy, Dallas, Texas; currently being restored & moved to the
Dallas Astronomical Society site in southern Oklahoma.
-Werner Von Braun in Huntsville, Alabama, still in its dome but missing some
parts & not functional, optics said to be superb.
-Naval Academy, Annapolis; now in a West Virginia public school (this example
noted at the Colgate U. website & not elsewhere).
In 1967, Ferson announced 3 new telescopes: 12 and 15 inch Maksutovs, and a
16 inch Cassegrain; all with three foci: Cassegrain, Cass-Coude, and Newtonian.
Single fork mounting, rotatable tube, electronically controlled drive with
positional readouts in declination and right ascension. Accessories included
spectrographs, photometers, cameras, and power supplies.
------
Sources:
Much of the Ferson material is from Tom Williams.
Ferson, Fred and Peter Lenart. Lens Production. Ingalls, Albert (editor).
Amateur Telescope Making, vol. 3. Richmond: Willmann-Bell, 1996; p. 35–75.
Ferson, Fred. Molding and Casting Springfield Mounting Parts. Pages 287 -
299. Ingalls, Albert (editor). Amateur Telescope Making, vol. 2. Richmond:
Willmann-Bell, 1996. (illustrated in figure B.6.4)
Ferson, Fred. Prisms, Flats, Mirrors. Pages 77 - 110. Ingalls, Albert
(editor). Amateur Telescope Making, vol. 3. Richmond: Willmann-Bell, 1996.
Sky and Telescope, advertisements: v38 #6 (June 1967) 389; v39 #3 (March 1968)
167; v39 #5 (May 1968) 334; v36 #1 (July 1968) 31.
===========================
GARDAM
William, Joseph, and Frederick Gardam made surveying instruments in New York
City from 1872 or 1878 to 1929. Their 1883 catalog includes astronomical
instruments such as equatorial mountings for telescopes up to 6 1/4 inches
aperture, and refers to an article in Scientific American 65 (1891) 345, 'A
Telescope for Schools and General Use' (a portable 4 inch equatorial).
Illustrated is a small refractor that is identical to the only known Gardam
telescope, a 4 inch in Mankato Minnesota.
Garcelon, David. William Gardam and Sons: Makers of Engineering, Surveying,
and Astronomical Instruments. Rittenhouse 9:2 (1995) 42-8.
Smart, Charles. The Makers of Surveying Instruments in America Since 1700.
Troy: Regal Art Press, 1962.
(A Telescope for Schools and General Use). Scientific American 65 (Nov. 28,
1891) 345.
=========================================
GAERTNER
William Gaertner worked for the instrument companies Repsold in Hamburg,
Breithaupt in Cassel, and Hilger in London, before emigrating to America. He
was selling laboratory apparatus, chemicals, and pharmaceuticals in the U.S. by
1882, and in June 1896 the instrument making firm of Kandler & Gaertner was
announced. Within a few years, William Gaertner and Company was founded at
5347-5349 Lake Avenue, Chicago, Illinois.
Catalogs:
--Instruments of Precision, Laboratory Apparatus, Astronomical Instruments,
1904, 70 pages.
--Astronomical Instruments and Accessories, 1908.
--Astronomical and Astrophysical Instruments, circa 1920, 48 pages: telescopes
to 12 inch aperture, mountings, accessories, transit telescopes, zenith
telescopes, photographic zenith telescopes, chronographs, comparators (numerous
varieties), solar - terrestrial orrery, celestial globes to 18 inches in
diameter.
--Interferometers and Interference Apparatus, circa 1928, 48 pages.
--Chronographs and accessories, 1930, 24 pages.
--Instruments of Precision, circa 1930, 90 pages.
====
From: John W. Briggs: Astrophysical Journal vol. 4 (June 1896) p83: "A New
Firm of Instrument Makers", seemingly written by G. E. Hale, who "took pleasure
in calling attention to the establishment in Chicago of a new firm of
instrument makers....Mssrs. Kandler and Gaertner". Hale indicates both of
these men were for a time employed in the workshop of Hale's personal and
short-lived Kenwood Observatory, which was in the back yard of his family's
mansion. At the University of Chicago, to this day, there is a "Gaertner Fund"
associated with the Department of Astronomy and Astrophysics. The Gaertner
Company is still in business, but they've recently moved from their original
site. Web address: http://www.gaertnerscientific.com/
Besides making instruments for schools, planetaria, and serious amateurs,
the firm made an amazing array of things, including measuring engines, for many
research observatories. For example, the large pit spectrograph associated
with the 60-foot solar tower at Mount Wilson was built by Gaertner, following a
Mount Wilson design.
A 9 inch Gaertner refractor has a Petitdidier objective, and another 9 inch
has a Brashear lens.
Three surviving 6 inch Gaertners -- at Smith College, Oberlin College, & one
in Indiana -- are exactly the same model, a photograph of which appears in F.
R. Moulton's well-known college astronomy textbook, as a standard example of an
equatorial. The design of this model seems very close to that of Warner &
Swasey.
The Smith College instrument dates from 1911, carries a Brashear lens, and
is now used by the Arunah Hill group.
The 6 1/8-inch Gaertner from Oberlin College in Ohio, now privately owned,
is in excellent condition, very complete with original weight drive, some
accessories, but no finder. The objective features quite a few bubbles and
unusually thin elements, suggesting that it might be an older lens remounted by
Gaertner.
The Indiana instrument carries a remounted lens by Harry Fitz, and it has
far more bubbles than any other I've seen. --John W. Briggs
====
From: Robert B. Ariail: In 1907 Wm. Gaertner & Co. became successors to
the Scientific Shop owned by Albert B. Porter and located at 324 Dearborn
Street, Chicago. This company sold a wide variety of optical parts, including
telescopic objectives and mirrors. The superintendent at that time was Francis
Gladheim Pease, who had already graduated from a technical college in Chicago,
in physics and mathematics, and had for six years been working with Yerkes
Observatory and the Carnegie Solar Observatory at Pasadena. Their 1907 catalog
stated: "With the exception of a few of the smaller items, the optical
materials listed in this catalogue are of our own manufacture......Our optical
works are well equipped woth modern machine tools, special glass working
machinery, testing devices, etc.....We are prepared to make objectives and
mirrors and build complete astronomical telescopes of modern design in the
largest sizes."
In 1923, the company was incorporated and became The Gaertner Scientific
Corporation, located at 1201 Wrightwood Avenue, Chicago, Illinois.
By 1928, the telescope portions of the catalogs were deleted and replaced by
a "listing" of several typed pages detailing the telescopes, accessories, and
prices. The largest was a 4-inch Equatorial Telescope with Clock, Circles and
Accessories, for $740. "The objective is of standard form....It is constructed
of the best optical glass obtainable, selected with due regard to durability
and corrected to eliminate chromatic and spherical aberration as completely as
the closest computation and the most unwearying patience can accomplish."
Gaertner acknowledged the "expertise provided in design and construction by
such luminaries as A.A. Michelson, F.L.O. Wadsworth and O.L. Petitdidier"
Petitdidier was encouraged to come to Chicago in 1898 by William Gaertner,
who wrote in the mid 1920s: "His shop was continued by us after his death in
1918 and, with the men trained by this great optician, and inproved and up-to-
date facilities, we have been able to continue to turn out the highest grade
and most accurate optical parts."
A circa 1920 catalog includes 'Stationary Equatorial Telescopes' -
professional grade six, eight, ten and twelve inch refractors. "We are
prepared to furnish complete observatory outfits including domes, observing
chairs. etc."
Gaertner telescopes used objectives both by Gaertner and by other makers. A
4 inch objective & cell by Lundin was mounted in a specially made Gaertner tube
in 1901. --Robert B. Ariail.
===========================================
HOWARD
Charles P. Howard, Hartford, Connecticut, 1880s to early 1900s. Amateur
astronomer & lens maker. Observed solar eclipse of 1900 with a group from
Trinity College, and published a booklet on this expedition to the southeast
U.S. where he mentions calculating and fabricating telescope objectives as
large as 7 inches aperture. He notes that he designed his lenses to avoid
reflections from the inner surfaces of the doublet or from the tube. This
would mean an R2 and R3 of slightly different radii, a characteristic that is
found in a surviving objective in a cell marked 'Made By C. P. Howard, Hartford
Conn.' This lens is 6 inches in diameter (clear aperture), flint forward, very
high quality but with unprofessional characteristics including lens edges that
are not chamfered to prevent chipping and rouge remaining on the edges. The
leading designer of flint forward objectives was Charles Hastings of Yale U.,
relatively close to Hartford.
Howard owned several significant telescopes, including a 9.4 inch Clark
equatorial refractor, purchased from D. W. Edgecomb in 1880, and sold in 1908
when he ordered a 12 inch Clark.
===========================================
JAEGERS
A. Jaegers, Ozone Park, New York, was selling raw optical glass and US
military surplus lenses & prisms, beginning before May, 1946, when a small
advertisement in Sky & Telescope was the first of 41 years of ads. By the mid
1950s, Jaegers was selling many models of binoculars and other optical
products; and also offering "hand-corrected, precision, American-made
astronomical objectives" made at the Jaegers plant, in 3 1/4 inch & 4 1/8 inch
apertures. By 1961, Jaegers had added 6 inch refractor objectives, f/10 and
f/15, at $175. coated and mounted. By 1965, Jaegers had two full pages in S &
T offering astronomical accessories and equipment from parabolic mirrors up to
10 inches, many binoculars, and objective lenses with prices remaining the
same. The 1970 address was in Lynbrook, N.Y. In April, 1987, there was a one
page ad in S & T, and the 6 inch coated & mounted objectives were $795. A
small ad in the May 1987 issue noted that a fire at the facilities of A.
Jaegers would delay both current and new orders, and that advertising and
notification would resume when the company returned to full production.
However, the plant had been destroyed, and the company did not resume business.
Jaegers objectives have been consistently excellent with first class color
correction and resolution, matching or exceeding Unitron objectives made in the
mid-sixties - another very good lens system; and far exceeding the Unitron
optics made in the decade of the 1970s - a very poor objective. However, the
Unitron objectives made in the 1950s based upon the Zeiss design, and with
superb quality control. may have been the best objectives made during that
period. --Robert B. Ariail
-------
As of early 2000, Jaegers was back in business, managed by Harry Peterson,
but without advertising, a catalogue or web site. Various sizes of objective
lenses are being produced. Circa 1997, 6 inch doublets, f/5, f/8/ or f/15,
were $1,070., without a cell. 5 inch f/5 cemented doublets were also in
production. A. Jaegers, 11 Roosevelt Ave., Valley Stream, N.Y., 11581; 516-
872-8111.
===========================================
MARTZ
From: Robert B. Ariail. Edwin P. Martz, Jr. was born in 1916 and as a
youth made his first mirror from a 6 inch glass disc given to him by his
father. Martz spent the next three years grinding, polishing and figuring the
mirror and finally achieved success, testing it by viewing a photograph of
Mars.
In December of 1935, Martz published 'An Investigation of the Relation of
Dust and Humidity to Planetary Definition', in an obscure & short lived monthly
periodical, 'The Chicago Bulletin' (which evolved into 'Amateur Astronomy',
published by the American Amateur Astronomical Association of Chicago, in
January 1936). Martz was on the editorial staff of the new publication from
the beginning, and became 'Planetary Director' of the monthly Planetary Report
column. He wrote monthly planetary reports over a three year period, on
amateur and professional work world-wide, including historical data on the
planets and the early astronomers who observed them. He also wrote for
'Popular Astronomy'.
In 1936, through the University of Chicago, Martz was offered the
opportunity to work with Dr. William Pickering at the Harvard Observatory in
Jamaica. In 1937, he studied Mars at Lowell Observatory in Flagstaff & Steward
observatory in Tucson; with further studies at Mount Wilson and Griffith
Observatories in Calif. By the end of 1937, he had a large collection of color
photographs of Mars.
Tom Cave remembers meeting Edwin Martz in the basement of the Adler
Planetarium during the summer of 1938.
From 1939 through 1941, Martz was an astronomer at the Dearborn observatory
of Northwestern University in Evanston, Ill., where he made early color
photographs of the planets.
During WWII, Martz was an officer and optical engineer with the U.S. Army
Air Corps at Wright Field in Ohio, where he was involved in development of
telescopic missile tracking systems. His two children, Carolyn and Larry, were
born in Dayton, Ohio during this period.
In early 1946, Martz moved to Inyokern, Calif., where he served as optical
engineer for the Naval Ordnance Test Station. He continued his work on missile
tracking systems until 1950, when he accepted jobs as optical physicist, first
for the Land-Air Corporation at the White Sands Integrated Range, New Mexico,
then for the U.S. Air Force Missile Development Center, at Holloman Air Force
Base.
From 1950 to 1958, the family lived in Alamogordo, NM, where Martz developed
missile tracking systems; and made optics for high altitude balloon
experiments, Aerobee missile shots, and rocket sled runs. Photography of these
projects was also a duty.
In 1952, Martz purchased a 12 inch (clear aperture) objective from Mr.
Hennessey for $750. It was an Alvan Clark lens, with widely separated
elements, in a Clark style cell. This objective is often described as from
West Point, although this is speculative at this point. In 1957, he designed
and built a large telescope for the 12 inch objective, in his back yard in
Alamogordo. His son Larry remembered viewing Jupiter and Saturn through this
telescope, but it was dismantled in 1958, when Martz and family moved to San
Diego. There he worked as research physicist for the Scripps Institution of
Oceanography and the Naval Undersea Laboratory. In 1960, he was offered the
position of Supervisor of the Space Optics Group at the Jet Propulsion
Laboratory, California Institute of Tehnology. During those years, he was
responsible for the telescopic lenses on the Ranger mooncraft. At the time of
his death, September 25, 1966, (1967 in another source), he was doing the
preliminary design for the Voyager camera systems. The two Voyagers were
launched with these vidicom cameras, and the pictures of Neptune displayed on
worldwide TV were produced using Martz's lens design.
Martz was an Associate member of the Royal Society of England, and a member
of the Optical Society of America. In 1964, he received the George W. Goddard
Award from the International Society for Optical Engineers, for his work in
aerospace photo-optical instrumentation technology.
In 1973, the U.S. Geological Society named a 91 km crater on the planet Mars
for Martz in recognition of his contributions to science.
The 12 inch Clark objective was donated to San Diego State University, where
it was dedicated in a new telescope and observatory on March 22, 1991; and
where it is used in astronomy classes to this day.
References:
Largely based on a speech given by Larry Martz at the Alvan Clark Objective
Dedication held at San Diego State University on March 22, 1991.
Ed Martz Jr. An Investigation of The Relation Of Dust and Humidity to
Planetary Definition. The Chicago Bulletin, Vol. 1, No. 4, December 1935.
Ed Martz Jr. Planetary Reports. Amateur Astronomy, Vol. 2, No. 1 - Vol. 4,
No. 6, January 1936-July 1938. (Monthly articles.)
---from Robert B. Ariail
------------------
From: Thomas R. Williams. Martz' early planetary observing was done with a
specially made long-focus six-inch Mellish Newtonian reflector with a Tolles
eyepiece. Martz studied astronomy at the University of Chicago, and as a
graduate student at Harvard, leaving after one year, and later gaining a
Master's degree at Northwestern. His observing in Arizona, at Lowell and
Steward observatories, and at Mt. Wilson and Griffith Park observatories in Los
Angeles, was not as a staff astronomer but part of his graduate research
program. During the period Martz was in Tucson, he experimented with a series
of multi-filter photographic images of the Catalina Mountains, exploring the
effects of dust & air pollution on atmospheric seeing and the use of filters as
an aid to planetary observing (monochromatic photos taken through colored
filters). --Tom Williams.
===============================================
PETITDIDIER
Octave Leon Petitdidier, born Villemagne, France, 1853; studied engineering,
moved to U.S. circa 1873. Worked as a civil engineer in Cincinnati, and in
1876 at the U. S. Engineer's Office in St. Louis & Indianapolis. Fabricated
two reflecting telescopes with mounts, 8 1/2 inch aperture; and a 6 inch
refractor for St. Louis University.
1894, in Mount Carmel, Illinois, issued catalog 'Portable Astronomical
Telescope', a 3 1/2 inch f/14 achromat, altazimuth mounting on wooden tripod.
1898, at 149 Fifty Sixth St., Chicago.
1899 Catalog, Astronomical and Terrestrial Telescopes, 6 pages. 2 1/2 to 3
1/2 inch refractors, alt-az and equatorial mounts, polarizing solar eyepieces.
1903, at 5423 Lake Ave., Chicago, next to William Gaertner & Co.
Circa 1908 catalog, Optical Parts, 12 pages. Doublet telescope objectives,
f/15, 2 inch ($12) to 15 inch ($3200). Doublet telescope objectives, f/18,
special glass, 3 inch ($60) to 10 inch ($1550). Triplet objectives, f/8 to
f/12, 3 inch ($80) to 8 inch ($1250). Four lens doublets, f/8, specifications
on request. Objective prisms. Parabolic mirrors, 6 inch f/10 ($35) to 20 inch
f/8.5 ($700). Spherical mirrors to 12 inches. Huyghenian eyepieces 'of our
own design'. Solid eyepieces. Optical flats, 1/10 wave, to 15 inches ($350).
Newton ring apparatus (a flat and a second plate that is convex by about 20
fringes), 3 inches diameter ($15). Prisms, right angle, to 5 inch by 5 inch
face ($150). Achromatic prism pair. Optical computations by Dr. Arthur C.
Lunn, U. Chicago mathematics department.
Fabricated many echelons for Albert Michelson's design of spectroscope;
these optical flats were up to 15 inches in diameter, of precise thickness, and
the two sides were parallel to 1/20 wavelength of light.
Petitdidier supplied optics for telescopes & other products of William
Gaertner & Co. He made a 9 inch telescope objective for the Indiana U., a 6
1/2 inch telescope objective for Boston U., and instruments for Lowell
Observatory.
He was of poor health, and died in 1918. The business was acquired by
Gaertner.
------
Warner, Deborah Jean. Octave Leon Petitdidier: Precision Optician.
Rittenhouse v9 #2 (Feb. 1995) 54-8
==============================================
SELLEW
Roland W. Sellew described himself as a 'Consulting Engineer', based in
Middletown, Connecticut, in his Engineering Catalog of May, 1924. Sellew was a
designer, not a fabricator, and acknowledges his contractors: 'Of the concerns
that have been engaged in making....items herein described....appreciation of
their aid.....' He lists some of his projects in this catalog:
The Yale U. Southern Telescope, 26 inch refractor, designed by Sellew & the
detail work fabricated at the Yale Observatory machine shop. Mount similar to
Dominon Astrophysical Obs. (English equatorial mount). Designed before final
choice of location, thus the pier head was adaptable to different latitudes.
Telescope tube of aluminum, 5 conical sections bolted at flanges. Aluminum
objective cell, outer lens element can be removed for cleaning.
Wellesley College small dome, built by Berlin Construction Co. 12.5 feet
inner diameter, motor driven via one of six ball bearing wheels. Steel ribs,
wood sheathing, sheet copper covering.
New type of observing chair, for Amherst College. A platform, 5' x 6', that
elevates on a 60 degree incline that follows the swing of the telescope
eyepiece. Electric motors for elevation & for traversing the floor.
New bearings & wheels for Amherst's small dome; weighing 9 tons but now
moveable by hand.
-------------------
Journal of Astronomical History and Heritage v1 #2 (Dec. 1998) 93-103
John Briggs and Donald Osterbrock.
The challenges and frustrations of a veteran astronomical optician: Robert
Lundin, 1880-1962 (excerpt).
...25.4 cm equatorial for the Elgar Weaver Observatory of Wittneberg College
(Popular Astronomy 41 (1933) 182-8).... a collaboration between Roland W
Sellew, a consulting engineer, and Robert Lundin. Sellew had in fact already
designed and presumably subcontracted the mechanical fabrication of instruments
for the Clark Corporation, in particular the 31.4-cm refractor built in 1927
for Columbia University (Sellew, 1929; Clark Corp., undated). A 1917 graduate
of the Sheffield Scientific School of Yale University, he had further
collaborated directly with Lundin on a 20.3-cm equatorial that was under
construction for the Kellogg Observatory of the new Buffalo Museum of Science
(Both, 1970). Unlike the Columbia telescope, however, the Buffalo and
Wittenberg instruments were not to be signed with Clark Corporation nameplates.
The Wittenberg astronomer, Hugh G. Harp, proceeded carefully in his
consideration of just what instrument to buy, seeking advice from many
experienced telescope users. Among the correspondents, Harvard's Harlow Shapley
(1929) replied, '... I would unhesitatingly recommend the work of Mr. Lundin,
at least with regard to optical parts; but some of the earlier work done by Mr.
Sellew was characterized more by cleverness than by the ability to complete his
contracts.'
Columbia's W. J. Eckert (1929) replied, '[Our] telescope and dome are in
general satisfactory, but several of the criticisms which have been made for
all the work done by these men apply equally well to our equipment. It seems
that both of these men are somewhat of the artistic temperament and are apt to
slip over details and, thus spoil a good job by some minor negligences.'
(Eckert went on to complain about his circle lights, the paint job, and other
small matters.)
But the most scathing reply came from Yale's Frank Schlesinger (1929): 'On
my return from Europe a few hours ago I find your letter of August 15. I have
no hesitation in saying that I should be very reluctant to entrust your
telescope to Mr. Sellew. He made drawings for our South African telescope ...
but it would have been impossible for him to do this without constant guidance,
supervision and restraint... I should say that Mr. Sellew needs much more
experience in all fases [sic] of telescope-making before his work will be
acceptable.'
Warren K Green (1929) of Amherst College was kinder regarding Lundin's
chosen collaborator: 'The work that Mr. Sellew did for me here [for the design
of our mechanized observing ladder] ... was very satisfactory. Since this was
his first attempt at astronomical work, he required a great deal of minute
direction; but, with the experience that he has had since, he should be able to
go ahead on his own initiative.'.......
However Sellew's difficulties reflect upon Lundin's judgment, C H Sawyer at
the Clark company was evidently growing concerned about Lundin's outside
collaborations. In a letter of January 22, Sawyer (1929) gave the president of
Wittenberg University price quotations for 20.3, 25.4 and 30.5-cm refractors. A
month later, Sawyer (1929) and Lundin (1929) both independently answered a
single letter from Harp, the Wittenberg astronomer. Two days later, Sawyer sent
Harp a draft of a contract, adding, 'Kindly address your reply to the writer at
20 Thorndike Street, East Cambridge [his home address] (Sawyer, 1929). And two
more days later, Harp read from Lundin, 'For the next few weeks, should you
wish to write me please address me at my home 173 School Street, Watertown,
Massachusetts' (Lundin, 1929). Finally, on April 8, Lundin wrote to Frederick
Slocum, director of Van Vleck Observatory, 'I wish to say to you that I have
severed my connections with the Alvan Clark & Sons Company and am establishing
myself in business under [my own name] and address.' (Lundin, 1929).
The Kellogg and Weaver Observatory instruments were eventually completed by
Lundin and Sellew, though the Sellew mountings were unsatisfactory by some
standards. After Lundin's departure from the Clark firm, Howard M Sawyer,
writing to Wittenberg College (1929), evidently had no choice but to say, 'We
thank you for giving [the Clark company] the opportunity to quote, but regret
that circumstances do not permit us to do so at this time.'
What was probably the last instrument in the saga of Lundin-Sellew
collaboration was an 22.2-cm refractor made for E W Rice, Jr., the honorary
chairman of the General Electric Company. Unlike the earlier mountings that
were signed 'Towner-Sellew Associates ... Objective and Optical Parts by C. A.
Robert Lundin,' the Rice instrument was signed simply 'C. A. Robert Lundin and
Associates.' In the few years Rice pursued astronomy on Fishers Island, New
York, before his death in 1935, he upgraded his lens to a Lundin 26.7 cm that
boasted a Hartmann criterion of 0.11, but then he finally replaced his entire
mounting with a sturdier one made by Warner & Swasey (Rice, 1934; Stearns,
1933).
-------------------------------
From: Robert B. Ariail: In the case of the Columbia U. 12 3/8-inch, it is
documented that Sellew (Middletown, Conn.) designed the dome housing this
instrument. It was built by The Berlin Construction Company, Inc., Berlin,
Conn., and by the Farrell Foundry and Machine Co., Ansonia, Conn. (Popular
Astronomy, Vol. XXXVI, No. 6, June-July, 1928). Although not mentioned or
confirmed in the PA article, this equatorial was surely designed by Sellew as
well as the dome. The article states, however: 'The equatorial was made by the
firm of Alvan Clark and is modern in every respect.......' It seems highly
unusual to me that Alvan Clark & Sons would manufacture a large mounting from a
design by Sellew or anyone else, but such may be the case; it has a large,
beautiful faceplate in brass signed in script with the Clark signature.
...This telescope & mounting is very large and heavy duty for a 12 3/8-inch.
The machining and fabrication of this telescope is not as sophisticated as the
Warner & Swasey or earlier Clark mounts, which were nicely engineered and
designed considering the period -- albeit undersized in some cases. A good
example is the right ascension worm gear mechanism on the Columbia U.
telescope. It is greatly undersized and a source of many problems with this
telescope in the past. Now in Columbia, S.C., a new gear, housing & components
must be re-engineered and manufactured to accomplish the necessary smoothness
and accuracy. Bob Ariail (slightly edited)
-----------------
From: Chris Ray. The 1926 Clark 12 3/8' refractor on a mount by Roland
Sellew, at Columbia, South Carolina. The tube alone weighs 684 lb and the cast
iron pier and mount approximateley 4000 lb. The declination axis alone weighs
272 lb. The dec axis when horizontal stands 11' 4' above the floor.....As we
assembled this telescope, I have studied the design of the mount by Sellew and
drawn it in detail. The structure is very strong. All shafts and control gears
are extra thick and rugged. The two axes run on large ball bearings. His worm
driver, however, is very poorly designed. The driver consists of a worm gear
on a shaft which is suspended on two conical points at each end, much like a
shaft would be mounted in a metal lathe between centers. That arrangement has
several defects which include lack of adequate lubrication and tendency to
become loose and eccentric in action on the points. It easily falls out of
alignment and requires constant manual lubrication of the points. It also binds
when either lateral or longitudnal pressure is applied. Furthermore the worm
assembly lacks precise adjustment to meet the worm wheel. Indeed, Columbia
complained that the telescope never tracked well. In addition, the worm driver
was run from shafts and gears coming up from the star drive in the pier which
were under-engineered and featured a single universal joint which in itself
would introduce a periodic error in the drive. Gayle Riggsbee is going to
machine a new worm driver on heavy bearings that I designed, powered by a
stepper gear motor mounted directly on its shaft, with roller thrust bearings
and a lubrication system and means to adjust it to the worm wheel. --Chris
Ray
---------------
From: John W. Briggs. Refractors designed by Sellew and carrying Robert
Lundin optics (but not signed as Clarks) include the 8-inch at the Buffalo
Museum of Science, the 10-inch at Weaver Observatory of Wittenberg University,
and the 8 3/4-inch built for E. W. Rice of General Electric (which, since about
1983, has been at 'Bogsucker Observatory' in Massachusetts).
I think Sellew was working under contract, or some such, for the Clark
Corp., when the 12 3/8-inch was designed. If one compares design features
between the Columbia 12 3/8-inch and the Rice 8 3/4-inch (the Rice 8 3/4-inch
being twin to the Buffalo instrument, and nearly twin to Wittenberg), one is
left with the overwhelming impression that one designer was involved.
Thus, I believe that Robert Lundin and Sellew got acquainted through their
collaboration on projects like the Columbia 12 3/8-inch. But when they started
doing too much work 'on the side' (i.e., the Wittenberg project) it led to
bitter conflict between Lundin and the Clark firm. Thus, Lundin quit the firm
in 1929 to set out on his own, in ongoing collaboration with Sellew.
The 8-inch refractor in Buffalo is at the Kellogg Observatory, which is atop
the local museum of science, has optics by Robert Lundin, and mechanicals by
'Towner-Sellew Associates' (per my limited memory of the exact words on the
plaque). I think Towner may have been a financial backer to Sellew's design
efforts. A similar plaque is on the Wittenberg instrument in Ohio.
In any case, by the time the same collaboration built the Rice 8 3/4-inch,
the plaque changed dramatically -- to 'C. A. Robert Lundin Associates,
Watertown, Mass.' The workmanship on the Rice instrument was 'fair.' Not bad
perhaps for an early model -- which would have been improved here and there, if
the firm had gone on for awhile. But the workmanship was clearly NOT
comparable to, say, the quality of a typical W&S. Also, some aspects of the
Wittenberg 10-inch (such as the small size of the original worm wheel) are
downright deplorable! As I recall, it's reasonably clear that the Rice
instrument is later than the Wittenberg one.
The Buffalo instrument, by the way, has been modified considerably over the
years, especially in its slow motions. Mr. E. Both, a curator emeritus there,
sent me detailed photos from their archives, which show the changes as years
went by. The 8 3/4-inch Rice instrument, which is essentially twin to the 8-
inch in Buffalo, remains mainly original. Last I saw, the Wittenberg telescope
was original, some 15 years ago.
Regarding the mechanized observing platform under the 18-inch at Amherst
College; I had chance to use the 18-inch a fair bit in the late 1970s --
Sellew's platform was a marvelous contraption! John W. Briggs
----------------
10-inch refracting telescope at Wittenberg University in Springfield, Ohio,
made around 1928 by C.A.R. Lundin. A plaque on the telescope pier says, 'Mount
and dome by Towner-Sellew.' There have been severe problems with the telescope
drive, reduced by careful balancing of the telescope, but the tracking is still
unacceptable. (From Wittenberg)
-------------------
From: Robert B. Ariail: Roland Sellew designed the mechanical features of
the observatory, including the dome, for the 16 inch compound reflector at
Melton Observatory, Univ. of S.C., Columbia. Completion of the observatory and
telescope was accomplished in early 1928. The equatorial is unusually large
for a 16-inch reflector, made by Bausch & Lomb, and is the largest B & L
equatorial seen by some experienced users. The optics are alleged to be by
Brashear, but this is highly unlikely; since the mirror is of relatively thin
plate glass, and has a mediocre figure, as revealed by foucaultgrams indicating
much less than a smooth parabola. In addition, it shows severe damage that may
have been caused by gross, improper cleaning at some point.
The observatory itself is quite attractive and was elevated to a good level
to clear the trees when it was installed. As Sellew stated: "The new
observatory building for the University Of South Carolina is one of the few of
its sort which will enhance rather than be detrimental to its surroundings." A
New Astronomical Observatory. Popular Astronomy. Vol. XXXVI, No. 8, October
1928, pp. 467-469.
=====================================
SPENCER
Charles Achilles Spencer (1813 -- 28 Sept. 1881), built his first microscope
at age 12. In 1838 he published an advertisement for reflecting telescopes of
various sizes, and a reflecting microscope. Spencer built both Gregorian and
Newtonian telescopes, 6 and 8 inches in aperture (Krauss). An 1840 catalog
listed 3 to 10 inch reflecting telescopes from $8 to $75, and 1 to 3 inch
refractors for $12 to $200 (Prices quoted from Smith, who includes some errors
in other sections; another source says that no copy of this catalog survives).
Smith wrote that Spencer was fascinated by astronomy and more inclined to
improve the telescope than the microscope, but found more room for innovation
with microscopes. Spencer was best known for his very high quality microscope
objectives; by 1851 had used fluorite for these, and he also manufactured small
quantities of glass at his workshop in Canastota N.Y. In 1850, Spencer
installed steam power and had 10 employees.
In 1854, with business partner Professor Asahel Eaton, he built a 13 1/2
inch refractor, 16 feet focal length, on an equatorial mount, for Hamilton
College, at a price of $10,000, with $1,000 of that used for scholarships at
Hamilton, where Spencer had studied for a period. The objective lens was
fabricated by Spencer employee August Stendicke, a German immigrant, who later
worked for Tolles. Spencer built a dividing engine to make the setting
circles. This was the largest telescope fabricated in the U.S. at the time.
Hamilton, in Clinton, N.Y., built a two story observatory with a cylindrical
dome 20 feet in diameter. Christian Peters used the telscope to study sunspots
and discover enough asteroids to win some fame & to motivate Mr. Litchfield to
donate funds for Peters' salary. Thus the observatory was renamed 'Litchfield
Observatory', but it was abandoned by the turn of the century, the instruments
(including the 13 1/2 inch objective) put in storage, and the building
demolished during World War I, leaving the equatorial's granite pier.
In 1856, Spencer & Eaton received a contract from Dudley observatory for a
split objective heliometer, at a cost of $14,500. Spencer traveled to
observatories in Europe for six months to prepare for this, but the order was
cancelled in the upcoming Dudley fiasco. Other telescope objectives by Spencer
& Eaton ranged from 3 to 5 inches in aperture. An 1868 advertisement was for
improvements in telescopes, including a pocket glass of under one inch
aperture. In 1870, Spencer sold 6 telescopes for $600. total, about one tenth
of his business. Fire destroyed the Canastota Spencer shop in 1873. He moved
to Geneva N.Y. in 1875, worked for Geneva Optical for one or two years,
meanwhile making microscope objectives signed Spencer.
Robert B. Tolles was a Spencer apprentice after about 1850. He opened his
own business in Boston in 1869, accompanied by Spencer's son Clarence.
Another son, Herbert Spencer (01 Nov. 1849 -- 07 Feb. 1900), worked for his
father, became a partner circa 1865, and in 1880 opened Herbert R. Spencer &
Co. in Geneva, with a 12 page catalog of microscopes, and also astronomical &
other telescopes, and field & opera glasses. In 1889, the business was moved
to Cleveland, advertising mounted telescopes and microscope objectives; and in
1891, Spencer & Smith Optical Co. was formed in Buffalo, becoming Spencer Lens
Co. in 1895.
Denver's Chamberlain Observatory includes a smaller dome that held a 6 inch
refractor on a Grubb pier for many years. The tube assembly is unmarked, but
the objective is marked Spencer Lens Co.1926 on the edge of the crown element
and Spencer Lens Co. 1936 on the edge of the flint element. This writing has
become extremely faint over time. The lens resembles a Littrow design, with
equiconvex crown and plano concave flint elements, the pair widely spaced, by
about 1 cm. This telescope is now mounted on the 20 inch Clark refractor, and
the pier is in storage.
References:
Gage, Simon. Microscopy in America 1830-1945. Transactions of the American
Microscopical Society 83:4 (Oct. 1964), Supplement.
Krauss, W.C. The Debt of American Microscopy to Spencer and Tolles.
Transactions of the American Microscopical Society (1902) 19-28. Reprinted in:
Three American Microscope Builders. Buffalo: American Optical Co., 1945.
Richards, Oscar. Charles A. Spencer and his Microscopes. Rittenhouse 2 (1988)
70-81.
Sheehan, William. Christian Heinrich Friedrich Peters; September 19, 1813--
July 18, 1890. Biographical Memoirs, National Academy of Sciences.
Smith, Hamilton. Memoir of Charles A. Spencer. Proceedings of the Society of
Microscopists (1882) 49-74. Reprinted in: Three American Microscope Builders.
Buffalo: American Optical Co., 1945.
====================================
THOMSON
Elihu Thomson.
Born 29 March, 1853 in Manchester, England; emigrated to Philadelphia,
U.S.A. in 1858; died 13 March, 1937 in Swampscott, Mass. An electrical
engineer with 692 patents, dated from 1876 to 1935, who made several
contributions to telescope optics. He was a co-founder of General Electric,
who financed his West Lynn, Mass., laboratory.
-----------
At age 13, Elihu used his cupola furnace to cast a droplet of glass for a
microscope lens. In 1874, while a high school teacher, he met a German
immigrant optician named Gerhardt at an exhibit at the Franklin Insitute, who
taught Elihu the techniques of optical fabrication. For Gerhardt, as a test,
he made a ten element microscope objective.
While teaching a Philadelphia's Central High School, he fabricated telescope
mirrors, developing the technique of grinding a concave glass mirror with a
convex glass tool (beginning with two flat discs), and publishing a 5 page
overview of mirror fabrication as 'A New Method of Grinding Glass Specula' in
1878. Thomson ground small lenses over the succeeding years.
He observed aurorae and sunspots, believing them to be connected, which at
the time was an unconventional belief.
Thomson travelled to Barnesville, Georgia for the 1900 eclipse of the sun,
and followed that with eclipses in Colorado, Spain, Norway, New England 1932,
and elsewhere. He viewed these events without attempting science or imaging.
Over a year, circa 1900, Thomson built a 10 inch equatorially mounted
refractor, using Mantois, Paris glass. He ground and polished the blanks on
machines of his own construction. The tube and mount were designed by Thomson,
contracting with a metals casting business for the large parts and machining
the clock drive on his lathe. In an observatory on the front lawn of his
Swampscott property, he began studying the skies, and Mars in particular.
Thomson disagreed with Lowell's conclusions regarding inhabitants on Mars. He
refigured his objective lens before the 1906 opposition of Mars and studied the
planet while invited observers made drawings of the surface using his
telescope. He developed a scheme to explain the color changes on Mars,
involving vegetation and animal life, wherein Lowell's 'canals' were
interpreted as paths taken by migrating animals.
[The 10 inch refractor is now owned by the Franklin Institute; it was loaned
to Ursinus College in the 1950s, used until the early 1990s, and is now in
storage at the College. The objective is still in excellent condition.]
Woodbury, p261, notes that Thomson published papers on telescope mirrors,
fused quartz, aurorae, comets, lunar craters, meteors, and the zodiacal light,
but no citations are provided. He wrote that the moon shows monthly changes in
surface color because of the extreme temperature variations it endures; and
that lunar craters were of meteoric origin, at a time when volcanic theories
were current.
Thomson became involved in Meteor Crater, Arizona, after meeting Daniel
Barringer in 1909, who at the time was advocating a meteoric origin for the
crater in opposition to the prevalent idea of a volcanic origin. Thomson
traveled to the crater in 1911 and wrote on the subject. Thomson's interest in
astronomy inspired Barringer to build a telescope and later publish an
astronomy newsletter, and the two corresponded extensively.
Circa 1902, Thomson began exploring alternative substrate materials for use
in telescope mirrors, and investigated fused quartz for its low-expansion
qualities. High temperature furnaces were designed & built at his laboratory
in Lynn to melt and cast quartz sand, producing disks of several inches in
diameter; but the quartz was very viscous when molten and could not be produced
without entrapping large quantities of small bubbles. George Hale wrote to
Thomson in 1903, proposing the use of fused quartz for optics in Hale's solar
telescopes (in 1904 the Mt. Wilson observatory was established with the Snow
solar telescope). Thomson supplied quartz mirror blanks to the MWO optical
shop, where they were fabricated into mirrors that were unsuccessful due to
bubbles. Decades of work on this problem followed; and eventually small blanks
of fused quartz were produced, but Thomson had hopes of very large quartz
mirrors that were never realized.
George Hale was a regular correspondent with Thomson; as were George Ritchey
and John Brashear; and many other contemporary astronomers exchanged letters
with Thomson. Sir Charles Parsons exchanged letters with Thomson on optical
glass.
During WWI, Thomson & staff worked with Bureau of Standards & optical
manufacturers in the development of optical glass for sights, range finders,
and binoculars (Woodbury p307). Thomson worked with S.W. Stratton and the
Bureau of Standards on the casting of a Pyrex blank for the 70 inch Perkins
telescope in 1926.
When the 200 inch Palomar telescope was in the early in the planning stages,
George Hale proposed a fused quartz mirror, and Thomson (at 75 years of age)
agreed to attempt to make several smaller prototypes and the actual 40 ton
mirror, at cost. The furnaces were of special design to achieve the 3000
degrees Fahrenheit needed to melt quartz, and the entire interior of the
furnace was a vacuum chamber intended to reduce the bubbles found in molten
quartz, which is very viscous and does not permit bubbles to float. The scheme
was to cast a disc and coat the top of it with bubble free quartz, and many
attempts, over several years, were met with failure. Niedergasse proposed that
the top layer be produced by spraying molten quartz in droplets onto the disk,
to build up a clear layer, and a hydrogen / oxygen blowtorch was designed and
built into the furnace. A 20 inch blank was successfully fabricated, but two
60 inch blanks failed to meet standards. After $600,000 had been spent on the
project, Hale stopped the process and chose Pyrex as a substrate. The
procedures developed were used in the widespread development of fused silica in
science & industry.
Thomson addressed the American Philosophical Society in Philadelphia in late
1929, and the speech was widely distributed. "Why the 200-inch Telescope"
understated the technical difficulties of working with quartz, and media
coverage ignored the problems and implied claims and statements that were far
too optimistic. The resulting publicity was highly counterproductive, and
Thomson remained very unhappy with media for the remainder of his life.
The above section is derived from David Woodbury's biography of Thomson and
his book on the Palomar telescope, and is therefore only mostly reliable. The
biography includes an uncredited image:
Elihu Thomson, image with 10 inch telescope at Swampscott:
http://home.europa.com/~telscope/thmsnts.jpg 240 kb.
-----------------------------
In 1899, experiments with fused quartz mirror blanks were begun, by
fabricating a convex mirror of glass and one of quartz, and passing a flame
over the back of each while viewing an artificial star. The glass mirror
quickly showed a distorted image, while the quartz mirror could be considerably
heated before the image was altered. Hale heard of this work, sent George
Ritchey to see Thomson in 1904, and provided $3,000. of Carnegie Institution
funds for further experiments. The Snow solar telescope was under construction
at this time, and quartz showed potential as a mirror for focusing sunlight.
However, the funds were spent before a successful mirror was produced, and the
project was continued on a small scale until the mid 1920s, when it was
abandoned. Especially promising was the possibility of expediting the
fabrication of a mirror by using low-expansion quartz; for in the final stages
of working a mirror, polishing heats the glass and the mirror must cool before
it can be tested, resulting in very long delays and slow progress.
When the 200 inch Palomar telescope was in the early planning stage, George
Hale favored fused silica for the mirror. In March of 1928, Hale met A. L.
Ellis of Thomson's laboratory, and received an estimate of $252,000 for work
resulting in a 200 inch quartz mirror. G.E. agreed to attempt production of
the mirror blank, at cost.
In 1904, Thomson was granted a patent for molding molten quartz. Quartz
sand was placed in a mold in a furnace equipped with vacuum pumps, but even the
partial vacuum did not remove the many bubbles found in the fused blanks.
Bubbles in the surface that was being worked would prevent an accurate profile
from being polished into shape. The solution seemed to be to form a coat or
layer of bubble free silica on top of a molten silica disc. By 1926, Thomson
had transferred the quartz experiments to A.L. Ellis, who used small rods of
clear quartz, cutting them into short cylinders and arraying them on the disk
in different patterns, but all efforts resulted in a clear surface that was
laced with striae and not acceptable.
Niedergasse thought that if very finely ground quartz was fed into a high
temperature flame, droplets of molten silica could be produced that could be
used to coat the disc; a scheme that had been tried by Thomson at the West Lynn
laboratories in an earlier project to produce artificial rubies and sapphires,
using alumina grains. After initiating the work on the Palomar telescope,
Thomson left the experiments and management to A.L. Ellis, and turned to other
tasks.
In 1929, Thomson proposed a ribbed back blank for the 200 inch, so that no
part of the disk was more than 4 inches from a surface, reducing cool-down
time. An active mounting system was part of this scheme, where a gravity-
operated lever mechanism pushed the ribs to compensate for deflection of the
mirror at different angles of altitude. Thomson designed counterweighted lever
arms in gimbals, that fit into each cell created by the ribs. The proposal was
refined in the coming years by John Anderson and other designers, and built
into the finished Palomar telescope. (Florence)
-----------
A 3 inch refractor with objective ground & polished by Thomson is
illustrated in a letter about the New Britain Scientific Association, in Sky &
Telescope 4:11 (Sept. 1940) 18.
Thomson corresponded with George Willis Ritchey, however only Ritchey's
replies survive, dating from 1910 to 1921. From them, we can deduce that some
of Ritchey's work with 'builtup' disks, of glass pieces cemented together with
sodium silicate to form a cellular mirror, was based on ideas from Thomson. He
also advised Ritchey on securing patents for the Ritchey-Chretien telescope.
In Oct. of 1912, Thomson sent Ritchey an unsolicited check for $250., and later
another for $50., to assist the development of the R-C; and advised the Rumford
Committee to award a $500. prize to Ritchey. (H. Abrahams)
----------
Abrahams, Harold. The Ritchey-Chretien Aplanatic Telescope: Letters from George
Willis Ritchey to Elihu Thomson. Proceedings of the American Philosophical
Society 116:6 (Dec. 1972) 486-501. (All text by Ritchey)
Florence, Ronald. The Perfect Machine: building the Palomar telescope. N.Y.:
Harper Collins, 1994.
Susskind, Charles. Thomson, Elihu. Dictionary of Scientific Biography.
Charles Gillispie, ed. New York: Scribner, 1970--.
Thomson, Elihu. A New Method of Grinding Glass Specula. Journal of the Franklin
Insititute 76 (Aug. 1878) 117-121.
Woodbury, David. Beloved Scientist: Elihu Thomson, a guiding spirit of the
electrical age. N.Y.: Whittlesey, 1944.
Woodbury, David. The Glass Giant of Palomar. N.Y.: Dodd, Mead, 1941.
---------
Additional sources:
Abrahams, Harold J., ed. Heroic efforts at Meteor Crater, Arizona : selected
correspondence between Daniel Moreau Barringer and Elihu Thomson. Rutherford:
Fairleigh Dickinson University Press, c1983. 322pp.
Abrahams, Harold J. and Marion B. Savin, ed. Selections From the Scientific
Correspondence of Elihu Thomson. Cambridge: MIT Press, 1971. Orbis: OSU
Valley TK140.T5 A4 1971. 'Limited to scientific interests, only obliquely on
technology'
Compton, Karl. Biographical memoir of Elihu Thomson, 1853-1937, by Karl T.
Compton. Presented to the academy at the autumn meeting, 1939. Washington,
D.C.: National Academy of Sciences, 1939. pp143-179. Biographical Memoirs,
National Academy of Sciences, v21, 4th memoir (1941) 143-179. "Selected list
of the publications of Elihu Thomson": p. 163-165.
Dictionary of American Biography, supp. 2, N.Y., 1958. pp657-659.
The National Cyclopaedia of American Biography, 27, N.Y., 1939, pp28-30.
Thomson papers at American Philosophical Society, Philadelphia.
====================================
TINSLEY
In 1926, Clayton R. Tinsley, a high school teacher, formed a company making
telescopes,mirrors and telescope making kits, in Berkeley, Calif.
A Tinsley Optical 12 inch Cassegrain telescope, circa 1929, was listed at
Mt. Wilson in 1932 and 1935, where astronomers found that the optics were
imperfect. It was then placed at the visitor's hotel at Mt. Wilson, later
owned by David Levy, and then Bill Marriot, who measured the primary at f/3.8 &
undercorrected, and polished the back of the secondary to find it full of
bubbles & striae, and of a spherical profile -- thus possibly a Dall-Kirkham.
Max Bray began his career in 1933, at Tinsley.
An undated catalog 'Supplies for the Amateur / Telescopes for School and
Home', address 3017 Wheeler St., Berkeley, was issued during the 1930s but
before 1937, when ATM 2 was published. Products are identical to the catalog
described below, but including draw tube spyglasses 7/8 inch to 2 1/4 inch
aperture, vulcanized fiber body. The 'Saturn' trademark was already in use.
Tinsley sold the company to Donald A. Jenkins in 1937.
An undated catalog, noting 'sixteen years of research and experience' (which
must reflect Clayton's pre-professional experiences), includes the ATM 2 book
and so is post 1937. It uses the 3017 Wheeler address, and an identical
catalog uses the address 2035 Ashby Ave., Berkeley. These catalogs list:
-Cassegrainian, f/16, equatorial on pier, electric clock drive, with 3 Ramsden
or Huyghenian eyepieces; 6 inch $390, 8 - 10 - 12 - 14 - 16 inch, 20 inch
$5500.
-Newtonian, f/8, equatorial on pier, electric clock drive, 6 inch, 8 inch; 10
inch $675.
-Four inch f/8 equatorial Newtonian, 'Saturn' mount, tripod, $175. Also
altazimuth mount.
-Equatorial mounts & rough castings for mounts, mirror cells, parabolic mirrors
4 to 12 inches, objective lenses to 4 inches, telescope making kits, mirror
blanks, objective lens blanks to 6 inches, eyepiece lens blanks, Foucault
tester, spherometer, focuser, terrestrial eyepiece, Ramsden & Huyghenian
eyepieces 1/4 inch to 2 inch focal length, solar Herschel wedge, prism & mirror
diagonals.
-Services: correction work on customer's mirrors, silvering mirrors using
Brashear process (lacquered on request); aluminizing using 'new Pancro
process', an alloy of magnesium and aluminum, overcoated with aluminum oxide
(panchromatic meaning true colors, reflectivity across the spectrum is superior
to aluminum).
During WWII, the company made binoculars and optical parts. The "Optical
Elements Code Chart, 9 March 1944, Ordnance Fire Control Sub-Office, Frankford
Arsenal", notes the glass parts were required to be identified by maker on the
rough ground edge of the optics, using a letter code in black ink or a color
code in 2 dots; Tinsley Laboratories codes being TLA, or white-green.
During 1946, Tinsley incorporated, and began manufacturing a line of
spotting telescopes and riflescopes.
Two inexpensive amateur refractors, on altazimuth mounts and wood tripods,
were introduced in 1955; a 44 mm for $48; and a 3 inch for $199. By 1955, the
address was 2350 Grove St., Berkeley, Calif.
An undated brochure for Tinsley Laboratories / Saturn Precision Telescopes,
uses the address 2526 Grove St., and notes a quarter century of experience.
-The Saturn Junior Refractor was 44 mm, 60 power with a 4 lens erecting
eyepiece, at $48.
-3 inch ($199) and 4 inch ($345) refractors, altaz on portable tripod.
-3 inch ($860), 4 inch ($1,185), and 5 inch ($2,750) f/15 refractors,
equatorial mounts.
-8 inch ($1,412), 10 inch ($2,148), and 12 inch ($3,480) Cassegrains, f/16,
equatorial mount on pier.
-6 inch ($960), 8 inch ($1,266), and 10 inch ($1,864) Newtonians, f/8,
equatorial mount on pier.
-Other unspecified products: Maksutovs, Schmidt systems, mounts, binoculars,
spotting scopes, eyepieces, flats, mirrors, lenses, prisms, Abbe prisms,
Wollaston prisms, Amici prisms, aluminizing and coating.
In 1957, Jenkins retired & sold the company to a group of employees and
investors. Tinsley then was producing telescopes for universities, and
Schlieren optical systems.
Tinsley became a public corporation in 1961.
A 20 inch triplet apochromatic refractor was made during 1963-4 for Ben
Morgan, who paid Tinsley about $250,000 for it, and sued Tinsley over its
performance. Lowell observatory purchased it circa 1963 for $100,000 or less,
where John Hall tested it and thought it was good enough. The objective was
returned to Tinsley for work once or twice; and taken to the U. of Arizona
optical shop, where Don Loomis reworked & respaced it. At Lowell, it was
intended for lunar mapping, but it was not a successful lens, and it need to be
stopped down to about 16 inches to provide a sharp image. The telescope is
shown in the Dec. 1964 S & T, p368, in a Tinsley ad, which describes it as
'ordered for lunar mapping'. The objective is now on display at Lowell, and
the dome & part of the mounting are still in use.
For Boeing, in the mid 1960s, Tinsley made a wide field optical collimator
using a modified Wright-Schmidt design, 18 inches aperture, with a 5 inch flat
focal plane. This was used in a vacuum housing, which gave the Schmidt
corrector plate the proper profile.
An undated brochure is devoted to The Tinsley Five Inch, Maksutov
Cassegrain, 5.65 inch primary, 5.1 inch corrector, f/15 overall, focuser uses a
Starrett micrometer, near focus 22 feet, single arm fork mount; DC variable
speed drive, rheostat speed control, rechargeable battery. $1450. Accessories
include a 'photographic module' camera adapter with flip out diagonal mirror,
which replaces the eyepiece housing.
A 12 inch Tinsley Cassegrain is being restored as of 2001 by the Peninsula
Astronomical Society near San Jose, Calif. Collimation is difficult because
the mirror cell has no adjustments for centering or tilting the primary; the
mirror is installed by placing the forward surface against a stop and the
telescope back is then bolted in place to hold the mirror. Speculation is that
the primary might be spherical and the system an exotic type of Cassegrain.
An 18 inch Tinsley cassegrain is in a private observatory in Idyllwild,
California, as of the 1980's.
The Mt. Cuba Observatory, (Greenville, Delaware) 24 inch Tinsley Cassegrain
is from 1964, and has f/16 and f/32 secondaries. A Baker corrector lens for
prime focus astrophotography yields a 7 degree field, but requires the primary
be stopped down to 20 inches, using a built in aperture ring in the mirror
cover. Most of the blueprints are copies of those for the U. Virginia 30 inch
telescope. The 'Richard B. Herr Memorial Telescope' is in active use to this
day. (From Emil Volcheck)
Brigham Young U. owns a 24 inch Tinsley.
Robinson Observatory of the Central Florida Astronomical Society owns a 26
inch Tinsley cassegrain, with a small hole in the back of the secondary, used
to align the secondary with the focuser by inserting a laser pointer or a
flashlight, to project a beam to the focuser. This telescope can be seen at
their web site: www.cfas.org
University of Virginia's McCormick Observatory, Fan Mountain station, has a
30 inch Tinsley Cassegrain with a 5 inch Tinsley Maksutov as a finder scope. A
source at U.V. is quoted that the mirror is 32 inches, but for prime focus work
is stopped down to 30 inches, because the Baker corrector lens shows distortion
at full aperture. U.V. has a student observatory on campus, that circa 1970
apparently housed a Tinsley 8 inch telescope that is now replaced.
The Fernbank Science Center, Atlanta, Georgia, has a 36 inch Tinsley.
The 1 meter Ritchey-Chretien telescope at USNO Flagstaff was designed &
built by George W. Ritchey, and completed in 1934. The Pyrex optics were
replaced with Corning fused quartz in 1969, and Tinsley figured the primary to
a modified concave hyperboloid, and the secondary to a modified convex
hyperboloid.
The Air Force Research Lab, Maui Space Surveillance Site, uses pair of
Tinsley 1.2 meter open tube classical Cassegrains (parabolic primary and
hyperbolic secondary), mounted on opposite sides of a single polar axis and
fixed to a common declination axis. See:
http://ulua.mhpcc.af.mil/AMOS/gallery.html
U. Michigan's 1.3 meter (52 inch) Tinsley reflector, installed 1969 at the
Portage Lake Observatory in Michigan, and was moved in the early 1970s to MDM
Observatory on Kitt Peak. Tinsley was the prime contractor, and figured the
optics from Cer-Vit (f/2.6 primary, secondaries, and two Coude flats). The
secondary rotates to switch between f/13.5 and f/7.6 Cassegrain optics, and a
third secondary is gimballed in place for f/33.5 Coude. The primary rests on
an 18 point cell, with radial support from six teflon coated steel straps, each
wrapping around 120 degrees of the mirror's circumference. The two pier
English mounting and major mechanical parts were done by L and F Machine Co.,
Huntington Park, Calif. The telescope is still in use every clear night. See
Sky & Telescope, Feb 1971, page 72. (from Patrick Seitzer)
A circa 1972 booklet notes the 34,000 square foot factory at 2448 Sixth St.,
Berkeley, built in 1961. Products included: A window for Skylab, 23 by 19 by
1 5/8 inches, transmitted wavefront lambda over 20 peak to peak; parallelism to
0.004 inch. Aluminum mirror, nickel plated, 23 feet diameter, f/1.9,
spherical, weight 14 tons, for Martin Marietta, 2 made. Beryllium mirrors,
nickel plated, 10 inch, polished to lambda over 10 peak to peak.
In 1972, Tinsley ceased production of telescopes, in favor of precision
optical systems and components, especially manufacture of aspheric optics. By
the 1990s, Tinsley was owned and operated by the Silicon Valley Group
http://www.asphere.com/
Tinsley made COSTAR (Corrective Optics Space Telescope Axial Replacement)
for the Space Telescope circa 1992. These were five pairs of mirrors placed
over the focal planes of the telescope instruments. Wavefront error was better
than 1/100 wave rms, and surface roughness was 4 to 5 Angstroms rms.
------
Sources: Tinsley catalogs & advertisements from Sky & Telescope. Email from
various sources. 'Historical Notes About Tinsley', email from the Tinsley
Corp., 1992.
====================================
TOLLES
Robert B. Tolles, was born 1822, 1823, or 1825 (various sources) in
Connecticut, and had little formal education. Circa 1843, he was apprenticed
to Charles Spencer, and in 1858 established his own business in Canastota N.Y.
By 1859, he was fabricating microscopes with Charles E. Grunow (most likely a
relative of the Grunow brothers, microscope makers), who made the mechanical
parts while Tolles made the objectives. An 1860 census notes three employees
and annual production of 6 microscopes ($600) and 68 objectives ($1778) by
Tolles. An inverted microscope won a prize in 1860.
An 1859 advertisement for microscope objectives includes notes on telescopes
and his solid eyepiece. Also described is an 'amplifier' that increases the
magnification of a microscope, provides a flat field, and reduces secondary
spectrum. This was a concave / convex lens inserted into the bottom of the
microscope draw tube; not a Tolles invention but much improved by him. In
1879, this amplifier was said to double the magnification of a particular
combination of objective and eyepiece without disturbing the corrections; and
that higher magnification amplifiers using a different design were also
available. Carpenter describes the amplifier thus (excerpts): 'a concave lens
between the objective and the eyepiece, magnifying power augmented, long since
introduced into telescopes, first made effective (microscopes) by Mr. Tolles,
an achromatic concavo-convex lens behind the objective, the power of which it
doubles'. Tolles' 1879 catalog lists an amplifier for telescopes, which would
be a Barlow or Smyth lens.
Tolles' solid eyepiece reduced glass / air surfaces to two by cementing two
planoconvex elements, and was used in telescopes and microscopes. It was
patented by Tolles in 1855 (U.S. 13,603), although Spencer was part of its
development and also manufactured them, and August Stendicke, a German lens
maker for Tolles and Spencer, knew of previous similar designs. The patent
does not cover all such cemented doublets, but only those with a focal plane
within the lens, at which point Tolles placed a reticle scale. The patent can
be found at the USPTO site: http://164.195.100.11/netahtml/srchnum.htm
The 1879 catalog lists the Tolles's Patent Solid Eye-piece in 1/2", 3/8", 1/4",
and 1/8" sizes at $8 and $12; and the Tolles's Solid Orthoscopic Eye-piece, 1
inch, with higher powers available, also useable as an achromatic condenser.
The major innovations of Tolles were in microscope optics. He pioneered the
immersion objective (homogeneous, meaning the liquid media was of similar
refractive index to glass); and fabricated very short focal length objectives
(to 1/75 inch), & of very high numerical aperture, up to 180 degrees 'angle of
aperture'. The correcting collar was developed by Tolles and Spencer, used to
correct spherical aberration introduced by differing thicknesses of cover
slips, using a ring on the barrel to move the center elements of the objective.
In 1866, Tolles developed a vertical illumination system, his 'interior
illuminator', that used a prism behind the front lens of the objective to
reflect light to the object. He patented a swinging substage, that varied the
angle of illumination above or below the stage; and two other microscope
illumination patents are 198,782 and 198,783.
Some of his objectives were comprised of seven individual lenses. Many
contemporary microscopists found his products to be the best in the world.
Tolles patented his binocular adapter in 1866, (U.S. Patent No. 56125),
priced at $80. in 1879, and sold for microscopes and also telescopes. This is
an unusual symmetrical design, where the light from the objective enters a
small equiangular prism placed at focus, and is split by the prism into two
deflected beams, which are then made parallel by two trapezoidal deflecting
prisms. Padgitt notes that Edmund Hartnack of Paris and Potsdam devised a
similar system at about the same time; and that Tolles' system was copied by
William Ladd and Abbe & Zeiss.
Circa 1864, Tolles made a small quantity of binoculars (no doubt Galilean
field glasses) for the U.S. Navy. James M. Gillis of the Navy wrote that they
were superior to European models but not good enough. This reference to an
otherwise completely unknown binocular is from a letter from Gillis to Alvan
Clark & Sons, noted in Warner & Ariail.
At an exhibition in Boston in 1865, Tolles displayed a telescope of 1 1/2
inches aperture, 4 1/2 inches focal length, with a binocular eyepiece providing
15 power, at $100. In 1867 was shown a 7/10 inch aperture, 4 inch focal
length, 13x telescope through which the satellites of Jupiter could be viewed.
By 1869, he had completed a 1 inch f/4 and a 1.45 inch f/4. These short focus
instruments were very unusual or unique in their time. An instrument described
as a Tolles micro-telescope in 1870 was a 1 inch f/6 objective with a small
microscope used as an erecting eyepiece, and providing 40 or 50 power.
In 1867, Tolles moved to Boston as a partner in Boston Optical Works,
incorporated with $9,000 in shares, at 66 Milk St., then 131 Devonshire St,
Boston. The company failed in 1871, at least partly because Tolles'
perfectionism was contrary to reasonable production schedules. He retained the
company name, located at 40 Hanover Street, working mostly by himself, with
only a few employees, including John Green, Orlando Amos, O.T. May (son in law
of Charles Spencer), and Clarence Spencer (son of Charles Spencer). Charles
Stodder had been selling Tolles' instruments since 1860, was treasurer of the
Works, and continued marketing Tolles' output.
The catalog: "Charles Stodder.....sole agent for the sale of Microscopes and
Telescopes made by R.B. Tolles", from 1879, includes the following telescopes:
--1/2 inch objective, solid eyepieces of 10x to 18x, 6.5 inches opened, $25,
$33 with stand, 'The Pedestrian's Telescope.'
--1 inch lens of 5 inch focus, pancratic eyepiece of 12x to 24x with higher
magnifications available, on stand, $70.
--2 1/2 inch lens, 22 to 27 inch focus, 23x to 46x pancratic eyepiece, alt / az
mount on iron tripod, $175; on engineers tripod $150; with two astronomical
eyepieces to 130x, amplifier, prism diagonal, and sun glass, $250, 'The High
School Telescope'.
--4 inch lens, on iron tripod, $300. Mentioned is a 4.1 inch of 42 inches
focal length, with an alt / az mount on an iron tripod.
--"Telescopes of any aperture, of unusually short focal length, made under
special contract"
The 1879 catalog includes a report from an 1869 exhibition in Boston, noting
that the Tolles binocular eyepiece can also be used in telescopes. On exhibit
were a 5 inch refractor of 35 inches focal length, on an equatorial mounting,
with 80x and 160x eyepieces; a 1 inch pancratic telescope of 4 to 12 inches
focal length; and a 1 1/2 inch refractor of 6 inch focal length. Telescopes
had been sold to Washington Academy, East Machias, Maine; Howland School, Union
Springs, N.Y.; and the High School in New Bedford, Mass.; various individuals
who were customers are also mentioned.
Also cited in the 1879 catalog is Benjamin Gould's 1871 report on viewing
15th magnitude stars from Cordoba, Argentina with his 5 inch f/7 tapered wood
tube, equatorial comet seeker. He also arranged the purchase of another Tolles
telescope for the Argentine National Observatory, which he directed. Gould
wrote in 1874 that he purchased his Tolles 'about a dozen years ago', and that
its field of 2 degrees allowed a view of the entire corona during the total
eclipse of 1869. "The telescope...has rendered important service in both
hemispheres." He later presented it to Seth Chandler, his assistant, whose
descendants gave it to the National Museum of American History, where it is
catalog 80.709.1
Charles X. Dalton was an employee of Tolles in Canastota, and after Tolles'
death 17 Nov. 1883, returned to the business to continue production of
microscopes. 'Charles X. Dalton, successor to the late R.B. Tolles, Boston
Optical Works', located at 30 and 48 Hanover Street, Boston, advertised in
1895, selling Tolles objectives and Tolles triplet magnifiers in silver cases.
Currently, a 5 inch refractor with a 45 inch tube and a Huygenian eyepiece
is located in the planetarium of the University of Maine.
References:
Blackham, George. Memoir of Robert B. Tolles. Proceedings of the American
Society of Microscopists (1884). Reprinted in: Three American Microscope
Builders. Buffalo: American Optical Co., 1945.
Carpenter, William. The Microscope and its Revelations. N.Y.: William Wood,
1883.
Gage, Simon. Microscopy in America 1830-1945. Transactions of the American
Microscopical Society 83:4 (Oct. 1964), Supplement.
Larue, Budd. Robert B. Tolles and the Cone-Fronted Objective. Rittenhouse 12
(1998) 55-64.
Padgitt, Donald L. A Short History of the Early American Microscopes.
Microscope Publications: London & Chicago, 1975.
Warner, Deborah Jean. The Microscopes and Telescopes of Robert B. Tolles.
Rittenhouse 9 (1995) 65-83.
Warner, Deborah Jean & Ariail, Robert B. Alvin Clark & Sons, Artists in
Optics, 2nd ed. Richmond: Willman-Bell, 1995.
Van Vleck, Richard. Robert B. Tolles, American Microscope Maker.
====================================
USNER
Charles F. Usner was primarily a manufacturer of photographic objectives.
Scientific American, September 13, 1879, had a cover story on the manufacture
of lenses at Usner, 128-130 Fulton St., New York. There was a note that
telescope objectives were one of Usner's products, but no further details on
telescopes. Usner made large, wet plate, portrait photographic lenses for
camera makers including Willard & Co. and Holmes, Booth, & Hayden.
A six inch portrait lens, a Petzval doublet of 36 inches focal length,
signed 'Willard', dated 1859, and made by Usner, had a field of 10-12 degrees
or 20 degrees, probably referring to usable field versus total field. The fast
f/6 focal ratio was designed for slow speed wet plate photography, but was
suited for astronomical work as well. The clear aperture was 5.85 inches,
reduced further with a four inch stop between the elements. The lens was used
by California amateur William Ireland to photograph the total solar eclipse of
January 1, 1889, from Norman, California. The plates revealed the solar corona
extending 2 1/2 degrees from the sun, and so impressed Edward Holden of Lick
Observatory that he purchased the lens, which was used after July 1889 by E.E.
Barnard for photography of comets and the Milky Way. At the end of 1889, the
lens was found by Barnard to be changed so that it produced penumbra around
stars, although probably the lens was simply more critically examined at years
end. Joel Metcalf wrote about this lens, that a portrait lens is designed so
that the visual rays (for focusing) come to the same focus as the
photographically active rays (bluer light), and that superior resolution and
color correction is achieved in a lens devoted to only one task. The lens was
sent to John Brashear for refiguring, who encountered difficulties in the job
but eventually returned an improved lens. In June of 1892, it was dedicated as
the Crocker Photographic Telescope, in a dedicated observatory on 'Huygens
Peak' at Mt. Hamilton, and used by Barnard for three years to image the Milky
Way and comets. The combination of lens and photographer produced photos that
were far superior to any made previously, published in 'Photographs of the
Milky Way and of Comets'. Barnard's long, hand guided exposures (4 hours for
example) and the wide field & high contrast of the lens, produced photographs
that revealed structures in the Milky Way that had never been seen before.
Barnard cataloged the dark nebulae that he found in the images, which are still
known by their 'B' numbers; although he clung to the mistaken idea that the
dark areas were actual vacancies in space, much later agreeing that they were
unilluminated areas of dust that block the passage of light (after his images
showed the dark nebulae to be blacker than starless sky). The lens and Barnard
also discovered structure in the tails of comets that was unprecedented,
leading him to suggest that cometary tails be used to explore the
interplanetary medium.
The current location of this lens is unknown.
Barnard's later work, and his finest photographs (Atlas of Selected Regions
of the Milky Way) were accomplished with the Bruce telescope, a 10 inch Petzval
lens by Brashear.
References:
Barnard, E.E. Publications of the Lick Observatory, vol. XI. Photographs
of the Milky Way and of Comets, made with the Six Inch Willard Lens and Crocker
Telescope, during the years 1892 to 1895, by E.E. Barnard. 1913.
Metcalf, Joel. Review of vol. XI, published by the Astronomical Society of
the Pacific, and found at: http://personal.tmlp.com/richard/asotp.htm
part of the Metcalf web page:
http://personal.tmlp.com/richard/metcalf.htm
Sheehan, William. The Immortal Fire Within: the life and work of Edward
Emerson Barnard. Cambridge: C.U.P., 1995.
====================================
WITHERSPOON
From: Robert B. Ariail, 06 Jun 2001
Earl Witherspoon. Sumter, South Carolina. Circa 1948, a large article was
published about Earl and his wonderful objective lenses in the Sumter Daily
Item. Earl was a professional lens maker who advertised in S & T on a fairly
regular basis. His first offering was probably in February 1948 when he
offered a 4-inch f/15 air-spaced doublet of "good quality" in a bronze cell for
$115. By March 1950 he was offering 4, 5, and 6 inch objectives in cells for
$60, $180, and $300 respectively, described as being of "first quality". By
July, 1951, the 4-inch objectives were discontinued, and edged blanks were
offered in all three sizes for $22.50, $32.50 and $45. By January of 1953, his
price for the 5 inch had increased to $200 and of the edged blanks only the 4
inch were offered. His business continued as such through August 1956 with
prices increasing to $220 and $325 for the 5 inch and 6 inch objectives in
cells with the edged 4 inch blanks reduced to $20. In January 1959, Earl
offered only mounted 6 inch objectives for $325. That was his last
advertisement, at a time of competition from Unitron, Jaegers, Fecker, Tinsley
and others.
In about 1963-64, I called and spoke with him and he invited me for a visit.
I journeyed to his home at 21 Warren Street in Sumter in the old section of
town. It was a large, two story frame old-time home as is still seen frequently
in the south. We sat on his front porch in rocking chairs and talked. As best
I recall, he was a soft spoken, pleasant man with a low key demeanor. He was
about 65 or slightly older with white hair and spent as much time with me as I
wanted. He was - as I suspected - completely out of the objective lens making
business. He had none available and had sold them all. He had also disposed
all of his equipment for making lenses and cells and was completely retired
from astronomy at that point. The only time he displayed any excitement during
our conversation was when he described how he shaped and polished the glass for
his objectives. He indicated that he had developed a technique that would very
quickly allow him to polish the glass and bring it to a perfect figure. I
remember how he 'lit up' when he described how he polished the glass and
brought it to a 'beautiful polish and excellent figure'. I remember distinctly
him proudly telling me that once in his lens making career, he began, early one
morning, working on a pair of rough blanks at the grinding stage. He worked
throughout the day and into the night with everything falling into place and
the various stages of grinding and polishing proceeding almost perfectly with
no setbacks. He then stated that late that night he had finished all the
stages of grinding, polishing, and figuring to his complete satisfaction for a
6 inch objective lens -- all accomplished in one day!
One intriguing story he interjected amid my constant questions about his
lenses and how he made them, was the fact that he was an observer as well. As
an observer he was a specialist - a comet seeker. He described as how for many
years he would go out every clear night with his telescope and search for
hours. In the winter he would wrap up with blankets and have his feet kept
warm by heated stones or bricks. He also admitted that although he observed
for many years, he never found a new comet.
Years later at Stellafane Conventions, I meet three different individuals
over several years who owned Witherspoon objectives and proudly proclaimed they
were of the highest quality. --Robert B. Ariail
------------
A current owner of a Witherspoon 6 inch f/17 describes it as of very high
quality.
==========================================
home page: http://www.europa.com/~telscope/binotele.htm